1VARNISHD(1) VARNISHD(1)
2
3
4
6 varnishd - HTTP accelerator daemon
7
9 varnishd [-a
10 [name=][address][:port][,PROTO][,user=<user>][,group=<group>][,mode=<mode>]]
11 [-b [host[:port]|path]] [-C] [-d] [-F] [-f config] [-h type[,options]]
12 [-I clifile] [-i identity] [-j jail[,jailoptions]] [-l vsl] [-M
13 address:port] [-n name] [-P file] [-p param=value] [-r
14 param[,param...]] [-S secret-file] [-s [name=]kind[,options]] [-T
15 address[:port]] [-t TTL] [-V] [-W waiter]
16
17 varnishd [-x parameter|vsl|cli|builtin|optstring]
18
19 varnishd [-?]
20
22 The varnishd daemon accepts HTTP requests from clients, passes them on
23 to a backend server and caches the returned documents to better satisfy
24 future requests for the same document.
25
27 Basic options
28 -a
29 <[name=][address][:port][,PROTO][,user=<user>][,group=<group>][,mode=<mode>]>
30 Listen for client requests on the specified address and port. The
31 address can be a host name ("localhost"), an IPv4 dotted-quad
32 ("127.0.0.1"), an IPv6 address enclosed in square brackets
33 ("[::1]"), or a path beginning with a '/' for a Unix domain socket
34 ("/path/to/listen.sock"). If address is not specified, varnishd will
35 listen on all available IPv4 and IPv6 interfaces. If port is not
36 specified, port 80 (http) is used. At least one of address or port
37 is required.
38
39 If a Unix domain socket is specified as the listen address, then the
40 user, group and mode sub-arguments may be used to specify the per‐
41 missions of the socket file -- use names for user and group, and a
42 3-digit octal value for mode. These sub-arguments are not permitted
43 if an IP address is specified. When Unix domain socket listeners are
44 in use, all VCL configurations must have version >= 4.1.
45
46 Name is referenced in logs. If name is not specified, "a0", "a1",
47 etc. is used. An additional protocol type can be set for the listen‐
48 ing socket with PROTO. Valid protocol types are: HTTP (default), and
49 PROXY.
50
51 Multiple listening addresses can be specified by using different -a
52 arguments.
53
54 -b <[host[:port]|path]>
55 Use the specified host as backend server. If port is not speci‐
56 fied, the default is 8080.
57
58 If the value of -b begins with /, it is interpreted as the abso‐
59 lute path of a Unix domain socket to which Varnish connects. In
60 that case, the value of -b must satisfy the conditions required
61 for the .path field of a backend declaration, see vcl(7). Back‐
62 ends with Unix socket addresses may only be used with VCL ver‐
63 sions >= 4.1.
64
65 -b can be used only once, and not together with f.
66
67 -f config
68 Use the specified VCL configuration file instead of the builtin
69 default. See vcl(7) for details on VCL syntax.
70
71 If a single -f option is used, then the VCL instance loaded from
72 the file is named "boot" and immediately becomes active. If more
73 than one -f option is used, the VCL instances are named "boot0",
74 "boot1" and so forth, in the order corresponding to the -f argu‐
75 ments, and the last one is named "boot", which becomes active.
76
77 Either -b or one or more -f options must be specified, but not
78 both, and they cannot both be left out, unless -d is used to
79 start varnishd in debugging mode. If the empty string is speci‐
80 fied as the sole -f option, then varnishd starts without start‐
81 ing the worker process, and the management process will accept
82 CLI commands. You can also combine an empty -f option with an
83 initialization script (-I option) and the child process will be
84 started if there is an active VCL at the end of the initializa‐
85 tion.
86
87 When used with a relative file name, config is searched in the
88 vcl_path. It is possible to set this path prior to using -f
89 options with a -p option. During startup, varnishd doesn't com‐
90 plain about unsafe VCL paths: unlike the varnish-cli(7) that
91 could later be accessed remotely, starting varnishd requires
92 local privileges.
93
94 -n name
95 Specify the name for this instance. This name is used to con‐
96 struct the name of the directory in which varnishd keeps tempo‐
97 rary files and persistent state. If the specified name begins
98 with a forward slash, it is interpreted as the absolute path to
99 the directory.
100
101 Documentation options
102 For these options, varnishd prints information to standard output and
103 exits. When a -x option is used, it must be the only option (it outputs
104 documentation in reStructuredText, aka RST).
105
106 -?
107 Print the usage message.
108
109 -x parameter
110 Print documentation of the runtime parameters (-p options), see
111 List of Parameters.
112
113 -x vsl Print documentation of the tags used in the Varnish shared mem‐
114 ory log, see vsl(7).
115
116 -x cli Print documentation of the command line interface, see var‐
117 nish-cli(7).
118
119 -x builtin
120 Print the contents of the default VCL program builtin.vcl.
121
122 -x optstring
123 Print the optstring parameter to getopt(3) to help writing wrap‐
124 per scripts.
125
126 Operations options
127 -F Do not fork, run in the foreground. Only one of -F or -d can be
128 specified, and -F cannot be used together with -C.
129
130 -T <address[:port]>
131 Offer a management interface on the specified address and port.
132 See varnish-cli(7) for documentation of the management commands.
133 To disable the management interface use none.
134
135 -M <address:port>
136 Connect to this port and offer the command line interface.
137 Think of it as a reverse shell. When running with -M and there
138 is no backend defined the child process (the cache) will not
139 start initially.
140
141 -P file
142 Write the PID of the process to the specified file.
143
144 -i identity
145 Specify the identity of the Varnish server. This can be accessed
146 using server.identity from VCL and with VSM_Name() from utili‐
147 ties. If not specified the output of gethostname(3) is used.
148
149 -I clifile
150 Execute the management commands in the file given as clifile
151 before the the worker process starts, see CLI Command File.
152
153 Tuning options
154 -t TTL Specifies the default time to live (TTL) for cached objects.
155 This is a shortcut for specifying the default_ttl run-time
156 parameter.
157
158 -p <param=value>
159 Set the parameter specified by param to the specified value, see
160 List of Parameters for details. This option can be used multiple
161 times to specify multiple parameters.
162
163 -s <[name=]type[,options]>
164 Use the specified storage backend. See Storage Backend section.
165
166 This option can be used multiple times to specify multiple stor‐
167 age files. Name is referenced in logs, VCL, statistics, etc. If
168 name is not specified, "s0", "s1" and so forth is used.
169
170 -l <vsl>
171 Specifies size of the space for the VSL records, shorthand for
172 -p vsl_space=<vsl>. Scaling suffixes like 'K' and 'M' can be
173 used up to (G)igabytes. See vsl_space for more information.
174
175 Security options
176 -r <param[,param...]>
177 Make the listed parameters read only. This gives the system
178 administrator a way to limit what the Varnish CLI can do. Con‐
179 sider making parameters such as cc_command, vcc_allow_inline_c
180 and vmod_path read only as these can potentially be used to
181 escalate privileges from the CLI.
182
183 -S secret-file
184 Path to a file containing a secret used for authorizing access
185 to the management port. To disable authentication use none.
186
187 If this argument is not provided, a secret drawn from the system
188 PRNG will be written to a file called _.secret in the working
189 directory (see opt_n) with default ownership and permissions of
190 the user having started varnish.
191
192 Thus, users wishing to delegate control over varnish will proba‐
193 bly want to create a custom secret file with appropriate permis‐
194 sions (ie. readable by a unix group to delegate control to).
195
196 -j <jail[,jailoptions]>
197 Specify the jailing mechanism to use. See Jail section.
198
199 Advanced, development and debugging options
200 -d Enables debugging mode: The parent process runs in the fore‐
201 ground with a CLI connection on stdin/stdout, and the child
202 process must be started explicitly with a CLI command. Terminat‐
203 ing the parent process will also terminate the child.
204
205 Only one of -d or -F can be specified, and -d cannot be used
206 together with -C.
207
208 -C Print VCL code compiled to C language and exit. Specify the VCL
209 file to compile with the -f option. Either -f or -b must be used
210 with -C, and -C cannot be used with -F or -d.
211
212 -V Display the version number and exit. This must be the only
213 option.
214
215 -h <type[,options]>
216 Specifies the hash algorithm. See Hash Algorithm section for a
217 list of supported algorithms.
218
219 -W waiter
220 Specifies the waiter type to use.
221
222 Hash Algorithm
223 The following hash algorithms are available:
224
225 -h critbit
226 self-scaling tree structure. The default hash algorithm in Var‐
227 nish Cache 2.1 and onwards. In comparison to a more traditional
228 B tree the critbit tree is almost completely lockless. Do not
229 change this unless you are certain what you're doing.
230
231 -h simple_list
232 A simple doubly-linked list. Not recommended for production
233 use.
234
235 -h <classic[,buckets]>
236 A standard hash table. The hash key is the CRC32 of the object's
237 URL modulo the size of the hash table. Each table entry points
238 to a list of elements which share the same hash key. The buckets
239 parameter specifies the number of entries in the hash table.
240 The default is 16383.
241
242 Storage Backend
243 The argument format to define storage backends is:
244
245 -s <[name]=kind[,options]>
246 If name is omitted, Varnish will name storages sN, starting with
247 s0 and incrementing N for every new storage.
248
249 For kind and options see details below.
250
251 Storages can be used in vcl as storage.name, so, for example if myStor‐
252 age was defined by -s myStorage=malloc,5G, it could be used in VCL like
253 so:
254
255 set beresp.storage = storage.myStorage;
256
257 A special name is Transient which is the default storage for
258 uncacheable objects as resulting from a pass, hit-for-miss or
259 hit-for-pass.
260
261 If no -s options are given, the default is:
262
263 -s malloc=100m
264
265 If no Transient storage is defined, the default is an unbound malloc
266 storage as if defined as:
267
268 -s Transient=malloc
269
270 The following storage types and options are available:
271
272 -s <default[,size]>
273 The default storage type resolves to umem where available and
274 malloc otherwise.
275
276 -s <malloc[,size]>
277 malloc is a memory based backend.
278
279 -s <umem[,size]>
280 umem is a storage backend which is more efficient than malloc on
281 platforms where it is available.
282
283 See the section on umem in chapter Storage backends of The Var‐
284 nish Users Guide for details.
285
286 -s <file,path[,size[,granularity[,advice]]]>
287 The file backend stores data in a file on disk. The file will be
288 accessed using mmap. Note that this storage provide no cache
289 persistence.
290
291 The path is mandatory. If path points to a directory, a tempo‐
292 rary file will be created in that directory and immediately
293 unlinked. If path points to a non-existing file, the file will
294 be created.
295
296 If size is omitted, and path points to an existing file with a
297 size greater than zero, the size of that file will be used. If
298 not, an error is reported.
299
300 Granularity sets the allocation block size. Defaults to the sys‐
301 tem page size or the filesystem block size, whichever is larger.
302
303 Advice tells the kernel how varnishd expects to use this mapped
304 region so that the kernel can choose the appropriate read-ahead
305 and caching techniques. Possible values are normal, random and
306 sequential, corresponding to MADV_NORMAL, MADV_RANDOM and
307 MADV_SEQUENTIAL madvise() advice argument, respectively.
308 Defaults to random.
309
310 -s <persistent,path,size>
311 Persistent storage. Varnish will store objects in a file in a
312 manner that will secure the survival of most of the objects in
313 the event of a planned or unplanned shutdown of Varnish. The
314 persistent storage backend has multiple issues with it and will
315 likely be removed from a future version of Varnish.
316
317 Jail
318 Varnish jails are a generalization over various platform specific meth‐
319 ods to reduce the privileges of varnish processes. They may have spe‐
320 cific options. Available jails are:
321
322 -j solaris
323 Reduce privileges(5) for varnishd and sub-process to the mini‐
324 mally required set. Only available on platforms which have the
325 setppriv(2) call.
326
327 -j <unix[,user=`user`][,ccgroup=`group`][,workuser=`user`]>
328 Default on all other platforms when varnishd is started with an
329 effective uid of 0 ("as root").
330
331 With the unix jail mechanism activated, varnish will switch to
332 an alternative user for subprocesses and change the effective
333 uid of the master process whenever possible.
334
335 The optional user argument specifies which alternative user to
336 use. It defaults to varnish.
337
338 The optional ccgroup argument specifies a group to add to var‐
339 nish subprocesses requiring access to a c-compiler. There is no
340 default.
341
342 The optional workuser argument specifies an alternative user to
343 use for the worker process. It defaults to vcache.
344
345 -j none
346 last resort jail choice: With jail mechanism none, varnish will
347 run all processes with the privileges it was started with.
348
349 Management Interface
350 If the -T option was specified, varnishd will offer a command-line man‐
351 agement interface on the specified address and port. The recommended
352 way of connecting to the command-line management interface is through
353 varnishadm(1).
354
355 The commands available are documented in varnish-cli(7).
356
357 CLI Command File
358 The -I option makes it possible to run arbitrary management commands
359 when varnishd is launched, before the worker process is started. In
360 particular, this is the way to load configurations, apply labels to
361 them, and make a VCL instance active that uses those labels on startup:
362
363 vcl.load panic /etc/varnish_panic.vcl
364 vcl.load siteA0 /etc/varnish_siteA.vcl
365 vcl.load siteB0 /etc/varnish_siteB.vcl
366 vcl.load siteC0 /etc/varnish_siteC.vcl
367 vcl.label siteA siteA0
368 vcl.label siteB siteB0
369 vcl.label siteC siteC0
370 vcl.load main /etc/varnish_main.vcl
371 vcl.use main
372
373 Every line in the file, including the last line, must be terminated by
374 a newline or carriage return.
375
376 If a command in the file is prefixed with '-', failure will not abort
377 the startup.
378
380 Run Time Parameter Flags
381 Runtime parameters are marked with shorthand flags to avoid repeating
382 the same text over and over in the table below. The meaning of the
383 flags are:
384
385 · experimental
386
387 We have no solid information about good/bad/optimal values for this
388 parameter. Feedback with experience and observations are most wel‐
389 come.
390
391 · delayed
392
393 This parameter can be changed on the fly, but will not take effect
394 immediately.
395
396 · restart
397
398 The worker process must be stopped and restarted, before this parame‐
399 ter takes effect.
400
401 · reload
402
403 The VCL programs must be reloaded for this parameter to take effect.
404
405 · experimental
406
407 We're not really sure about this parameter, tell us what you find.
408
409 · wizard
410
411 Do not touch unless you really know what you're doing.
412
413 · only_root
414
415 Only works if varnishd is running as root.
416
417 Default Value Exceptions on 32 bit Systems
418 Be aware that on 32 bit systems, certain default or maximum values are
419 reduced relative to the values listed below, in order to conserve VM
420 space:
421
422 · workspace_client: 24k
423
424 · workspace_backend: 20k
425
426 · http_resp_size: 8k
427
428 · http_req_size: 12k
429
430 · gzip_buffer: 4k
431
432 · vsl_space: 1G (maximum)
433
434 · thread_pool_stack: 52k
435
436 List of Parameters
437 This text is produced from the same text you will find in the CLI if
438 you use the param.show command:
439
440 accept_filter
441 NB: This parameter depends on a feature which is not available on all
442 platforms.
443
444 · Units: bool
445
446 · Default: on (if your platform supports accept filters)
447
448 Enable kernel accept-filters. This may require a kernel module to be
449 loaded to have an effect when enabled.
450
451 Enabling accept_filter may prevent some requests to reach Varnish in
452 the first place. Malformed requests may go unnoticed and not increase
453 the client_req_400 counter. GET or HEAD requests with a body may be
454 blocked altogether.
455
456 acceptor_sleep_decay
457 · Default: 0.9
458
459 · Minimum: 0
460
461 · Maximum: 1
462
463 · Flags: experimental
464
465 If we run out of resources, such as file descriptors or worker threads,
466 the acceptor will sleep between accepts. This parameter (multiplica‐
467 tively) reduce the sleep duration for each successful accept. (ie: 0.9
468 = reduce by 10%)
469
470 acceptor_sleep_incr
471 · Units: seconds
472
473 · Default: 0.000
474
475 · Minimum: 0.000
476
477 · Maximum: 1.000
478
479 · Flags: experimental
480
481 If we run out of resources, such as file descriptors or worker threads,
482 the acceptor will sleep between accepts. This parameter control how
483 much longer we sleep, each time we fail to accept a new connection.
484
485 acceptor_sleep_max
486 · Units: seconds
487
488 · Default: 0.050
489
490 · Minimum: 0.000
491
492 · Maximum: 10.000
493
494 · Flags: experimental
495
496 If we run out of resources, such as file descriptors or worker threads,
497 the acceptor will sleep between accepts. This parameter limits how
498 long it can sleep between attempts to accept new connections.
499
500 auto_restart
501 · Units: bool
502
503 · Default: on
504
505 Automatically restart the child/worker process if it dies.
506
507 backend_idle_timeout
508 · Units: seconds
509
510 · Default: 60.000
511
512 · Minimum: 1.000
513
514 Timeout before we close unused backend connections.
515
516 backend_local_error_holddown
517 · Units: seconds
518
519 · Default: 10.000
520
521 · Minimum: 0.000
522
523 · Flags: experimental
524
525 When connecting to backends, certain error codes (EADDRNOTAVAIL, EAC‐
526 CESS, EPERM) signal a local resource shortage or configuration issue
527 for which retrying connection attempts may worsen the situation due to
528 the complexity of the operations involved in the kernel. This parame‐
529 ter prevents repeated connection attempts for the configured duration.
530
531 backend_remote_error_holddown
532 · Units: seconds
533
534 · Default: 0.250
535
536 · Minimum: 0.000
537
538 · Flags: experimental
539
540 When connecting to backends, certain error codes (ECONNREFUSED, ENETUN‐
541 REACH) signal fundamental connection issues such as the backend not
542 accepting connections or routing problems for which repeated connection
543 attempts are considered useless This parameter prevents repeated con‐
544 nection attempts for the configured duration.
545
546 ban_cutoff
547 · Units: bans
548
549 · Default: 0
550
551 · Minimum: 0
552
553 · Flags: experimental
554
555 Expurge long tail content from the cache to keep the number of bans
556 below this value. 0 disables.
557
558 When this parameter is set to a non-zero value, the ban lurker contin‐
559 ues to work the ban list as usual top to bottom, but when it reaches
560 the ban_cutoff-th ban, it treats all objects as if they matched a ban
561 and expurges them from cache. As actively used objects get tested
562 against the ban list at request time and thus are likely to be associ‐
563 ated with bans near the top of the ban list, with ban_cutoff, least
564 recently accessed objects (the "long tail") are removed.
565
566 This parameter is a safety net to avoid bad response times due to bans
567 being tested at lookup time. Setting a cutoff trades response time for
568 cache efficiency. The recommended value is proportional to
569 rate(bans_lurker_tests_tested) / n_objects while the ban lurker is
570 working, which is the number of bans the system can sustain. The addi‐
571 tional latency due to request ban testing is in the order of ban_cutoff
572 / rate(bans_lurker_tests_tested). For example, for
573 rate(bans_lurker_tests_tested) = 2M/s and a tolerable latency of 100ms,
574 a good value for ban_cutoff may be 200K.
575
576 ban_dups
577 · Units: bool
578
579 · Default: on
580
581 Eliminate older identical bans when a new ban is added. This saves CPU
582 cycles by not comparing objects to identical bans. This is a waste of
583 time if you have many bans which are never identical.
584
585 ban_lurker_age
586 · Units: seconds
587
588 · Default: 60.000
589
590 · Minimum: 0.000
591
592 The ban lurker will ignore bans until they are this old. When a ban is
593 added, the active traffic will be tested against it as part of object
594 lookup. Because many applications issue bans in bursts, this parameter
595 holds the ban-lurker off until the rush is over. This should be set to
596 the approximate time which a ban-burst takes.
597
598 ban_lurker_batch
599 · Default: 1000
600
601 · Minimum: 1
602
603 The ban lurker sleeps ${ban_lurker_sleep} after examining this many
604 objects. Use this to pace the ban-lurker if it eats too many
605 resources.
606
607 ban_lurker_holdoff
608 · Units: seconds
609
610 · Default: 0.010
611
612 · Minimum: 0.000
613
614 · Flags: experimental
615
616 How long the ban lurker sleeps when giving way to lookup due to lock
617 contention.
618
619 ban_lurker_sleep
620 · Units: seconds
621
622 · Default: 0.010
623
624 · Minimum: 0.000
625
626 How long the ban lurker sleeps after examining ${ban_lurker_batch}
627 objects. Use this to pace the ban-lurker if it eats too many
628 resources. A value of zero will disable the ban lurker entirely.
629
630 between_bytes_timeout
631 · Units: seconds
632
633 · Default: 60.000
634
635 · Minimum: 0.000
636
637 We only wait for this many seconds between bytes received from the
638 backend before giving up the fetch. VCL values, per backend or per
639 backend request take precedence. This parameter does not apply to
640 pipe'ed requests.
641
642 cc_command
643 · Default: defined when Varnish is built
644
645 · Flags: must_reload
646
647 Command used for compiling the C source code to a dlopen(3) loadable
648 object. Any occurrence of %s in the string will be replaced with the
649 source file name, and %o will be replaced with the output file name.
650
651 cli_limit
652 · Units: bytes
653
654 · Default: 48k
655
656 · Minimum: 128b
657
658 · Maximum: 99999999b
659
660 Maximum size of CLI response. If the response exceeds this limit, the
661 response code will be 201 instead of 200 and the last line will indi‐
662 cate the truncation.
663
664 cli_timeout
665 · Units: seconds
666
667 · Default: 60.000
668
669 · Minimum: 0.000
670
671 Timeout for the childs replies to CLI requests from the mgt_param.
672
673 clock_skew
674 · Units: seconds
675
676 · Default: 10
677
678 · Minimum: 0
679
680 How much clockskew we are willing to accept between the backend and our
681 own clock.
682
683 clock_step
684 · Units: seconds
685
686 · Default: 1.000
687
688 · Minimum: 0.000
689
690 How much observed clock step we are willing to accept before we panic.
691
692 connect_timeout
693 · Units: seconds
694
695 · Default: 3.500
696
697 · Minimum: 0.000
698
699 Default connection timeout for backend connections. We only try to con‐
700 nect to the backend for this many seconds before giving up. VCL can
701 override this default value for each backend and backend request.
702
703 critbit_cooloff
704 · Units: seconds
705
706 · Default: 180.000
707
708 · Minimum: 60.000
709
710 · Maximum: 254.000
711
712 · Flags: wizard
713
714 How long the critbit hasher keeps deleted objheads on the cooloff list.
715
716 debug
717 · Default: none
718
719 Enable/Disable various kinds of debugging.
720
721 none Disable all debugging
722
723 Use +/- prefix to set/reset individual bits:
724
725 req_state
726 VSL Request state engine
727
728 workspace
729 VSL Workspace operations
730
731 waitinglist
732 VSL Waitinglist events
733
734 syncvsl
735 Make VSL synchronous
736
737 hashedge
738 Edge cases in Hash
739
740 vclrel Rapid VCL release
741
742 lurker VSL Ban lurker
743
744 esi_chop
745 Chop ESI fetch to bits
746
747 flush_head
748 Flush after http1 head
749
750 vtc_mode
751 Varnishtest Mode
752
753 witness
754 Emit WITNESS lock records
755
756 vsm_keep
757 Keep the VSM file on restart
758
759 drop_pools
760 Drop thread pools (testing)
761
762 slow_acceptor
763 Slow down Acceptor
764
765 h2_nocheck
766 Disable various H2 checks
767
768 vmod_so_keep
769 Keep copied VMOD libraries
770
771 processors
772 Fetch/Deliver processors
773
774 protocol
775 Protocol debugging
776
777 vcl_keep
778 Keep VCL C and so files
779
780 lck Additional lock statistics
781
782 default_grace
783 · Units: seconds
784
785 · Default: 10.000
786
787 · Minimum: 0.000
788
789 · Flags: obj_sticky
790
791 Default grace period. We will deliver an object this long after it has
792 expired, provided another thread is attempting to get a new copy.
793
794 default_keep
795 · Units: seconds
796
797 · Default: 0.000
798
799 · Minimum: 0.000
800
801 · Flags: obj_sticky
802
803 Default keep period. We will keep a useless object around this long,
804 making it available for conditional backend fetches. That means that
805 the object will be removed from the cache at the end of ttl+grace+keep.
806
807 default_ttl
808 · Units: seconds
809
810 · Default: 120.000
811
812 · Minimum: 0.000
813
814 · Flags: obj_sticky
815
816 The TTL assigned to objects if neither the backend nor the VCL code
817 assigns one.
818
819 feature
820 · Default: none
821
822 Enable/Disable various minor features.
823
824 none Disable all features.
825
826 Use +/- prefix to enable/disable individual feature:
827
828 short_panic
829 Short panic message.
830
831 wait_silo
832 Wait for persistent silo.
833
834 no_coredump
835 No coredumps.
836
837 esi_ignore_https
838 Treat HTTPS as HTTP in ESI:includes
839
840 esi_disable_xml_check
841 Don't check of body looks like XML
842
843 esi_ignore_other_elements
844 Ignore non-esi XML-elements
845
846 esi_remove_bom
847 Remove UTF-8 BOM
848
849 https_scheme
850 Also split https URIs
851
852 http2 Support HTTP/2 protocol
853
854 http_date_postel
855 Relax parsing of timestamps in HTTP headers
856
857 fetch_chunksize
858 · Units: bytes
859
860 · Default: 16k
861
862 · Minimum: 4k
863
864 · Flags: experimental
865
866 The default chunksize used by fetcher. This should be bigger than the
867 majority of objects with short TTLs. Internal limits in the stor‐
868 age_file module makes increases above 128kb a dubious idea.
869
870 fetch_maxchunksize
871 · Units: bytes
872
873 · Default: 0.25G
874
875 · Minimum: 64k
876
877 · Flags: experimental
878
879 The maximum chunksize we attempt to allocate from storage. Making this
880 too large may cause delays and storage fragmentation.
881
882 first_byte_timeout
883 · Units: seconds
884
885 · Default: 60.000
886
887 · Minimum: 0.000
888
889 Default timeout for receiving first byte from backend. We only wait for
890 this many seconds for the first byte before giving up. VCL can over‐
891 ride this default value for each backend and backend request. This
892 parameter does not apply to pipe'ed requests.
893
894 gzip_buffer
895 · Units: bytes
896
897 · Default: 32k
898
899 · Minimum: 2k
900
901 · Flags: experimental
902
903 Size of malloc buffer used for gzip processing. These buffers are used
904 for in-transit data, for instance gunzip'ed data being sent to a
905 client.Making this space to small results in more overhead, writes to
906 sockets etc, making it too big is probably just a waste of memory.
907
908 gzip_level
909 · Default: 6
910
911 · Minimum: 0
912
913 · Maximum: 9
914
915 Gzip compression level: 0=debug, 1=fast, 9=best
916
917 gzip_memlevel
918 · Default: 8
919
920 · Minimum: 1
921
922 · Maximum: 9
923
924 Gzip memory level 1=slow/least, 9=fast/most compression. Memory impact
925 is 1=1k, 2=2k, ... 9=256k.
926
927 h2_header_table_size
928 · Units: bytes
929
930 · Default: 4k
931
932 · Minimum: 0b
933
934 HTTP2 header table size. This is the size that will be used for the
935 HPACK dynamic decoding table.
936
937 h2_initial_window_size
938 · Units: bytes
939
940 · Default: 65535b
941
942 · Minimum: 0b
943
944 · Maximum: 2147483647b
945
946 HTTP2 initial flow control window size.
947
948 h2_max_concurrent_streams
949 · Units: streams
950
951 · Default: 100
952
953 · Minimum: 0
954
955 HTTP2 Maximum number of concurrent streams. This is the number of
956 requests that can be active at the same time for a single HTTP2 connec‐
957 tion.
958
959 h2_max_frame_size
960 · Units: bytes
961
962 · Default: 16k
963
964 · Minimum: 16k
965
966 · Maximum: 16777215b
967
968 HTTP2 maximum per frame payload size we are willing to accept.
969
970 h2_max_header_list_size
971 · Units: bytes
972
973 · Default: 2147483647b
974
975 · Minimum: 0b
976
977 HTTP2 maximum size of an uncompressed header list.
978
979 h2_rx_window_increment
980 · Units: bytes
981
982 · Default: 1M
983
984 · Minimum: 1M
985
986 · Maximum: 1G
987
988 · Flags: wizard
989
990 HTTP2 Receive Window Increments. How big credits we send in WIN‐
991 DOW_UPDATE frames Only affects incoming request bodies (ie: POST, PUT
992 etc.)
993
994 h2_rx_window_low_water
995 · Units: bytes
996
997 · Default: 10M
998
999 · Minimum: 65535b
1000
1001 · Maximum: 1G
1002
1003 · Flags: wizard
1004
1005 HTTP2 Receive Window low water mark. We try to keep the window at
1006 least this big Only affects incoming request bodies (ie: POST, PUT
1007 etc.)
1008
1009 http1_iovs
1010 · Units: struct iovec (=16 bytes)
1011
1012 · Default: 64
1013
1014 · Minimum: 5
1015
1016 · Maximum: 1024
1017
1018 · Flags: wizard
1019
1020 Number of io vectors to allocate for HTTP1 protocol transmission. A
1021 HTTP1 header needs 7 + 2 per HTTP header field. Allocated from
1022 workspace_thread.
1023
1024 http_gzip_support
1025 · Units: bool
1026
1027 · Default: on
1028
1029 Enable gzip support. When enabled Varnish request compressed objects
1030 from the backend and store them compressed. If a client does not sup‐
1031 port gzip encoding Varnish will uncompress compressed objects on
1032 demand. Varnish will also rewrite the Accept-Encoding header of clients
1033 indicating support for gzip to:
1034 Accept-Encoding: gzip
1035
1036 Clients that do not support gzip will have their Accept-Encoding header
1037 removed. For more information on how gzip is implemented please see the
1038 chapter on gzip in the Varnish reference.
1039
1040 When gzip support is disabled the variables beresp.do_gzip and
1041 beresp.do_gunzip have no effect in VCL.
1042
1043 http_max_hdr
1044 · Units: header lines
1045
1046 · Default: 64
1047
1048 · Minimum: 32
1049
1050 · Maximum: 65535
1051
1052 Maximum number of HTTP header lines we allow in
1053 {req|resp|bereq|beresp}.http (obj.http is autosized to the exact number
1054 of headers). Cheap, ~20 bytes, in terms of workspace memory. Note
1055 that the first line occupies five header lines.
1056
1057 http_range_support
1058 · Units: bool
1059
1060 · Default: on
1061
1062 Enable support for HTTP Range headers.
1063
1064 http_req_hdr_len
1065 · Units: bytes
1066
1067 · Default: 8k
1068
1069 · Minimum: 40b
1070
1071 Maximum length of any HTTP client request header we will allow. The
1072 limit is inclusive its continuation lines.
1073
1074 http_req_size
1075 · Units: bytes
1076
1077 · Default: 32k
1078
1079 · Minimum: 0.25k
1080
1081 Maximum number of bytes of HTTP client request we will deal with. This
1082 is a limit on all bytes up to the double blank line which ends the HTTP
1083 request. The memory for the request is allocated from the client
1084 workspace (param: workspace_client) and this parameter limits how much
1085 of that the request is allowed to take up.
1086
1087 http_resp_hdr_len
1088 · Units: bytes
1089
1090 · Default: 8k
1091
1092 · Minimum: 40b
1093
1094 Maximum length of any HTTP backend response header we will allow. The
1095 limit is inclusive its continuation lines.
1096
1097 http_resp_size
1098 · Units: bytes
1099
1100 · Default: 32k
1101
1102 · Minimum: 0.25k
1103
1104 Maximum number of bytes of HTTP backend response we will deal with.
1105 This is a limit on all bytes up to the double blank line which ends the
1106 HTTP response. The memory for the response is allocated from the back‐
1107 end workspace (param: workspace_backend) and this parameter limits how
1108 much of that the response is allowed to take up.
1109
1110 idle_send_timeout
1111 · Units: seconds
1112
1113 · Default: 60.000
1114
1115 · Minimum: 0.000
1116
1117 · Flags: delayed
1118
1119 Send timeout for individual pieces of data on client connections. May
1120 get extended if 'send_timeout' applies.
1121
1122 When this timeout is hit, the session is closed.
1123
1124 See the man page for setsockopt(2) or socket(7) under SO_SNDTIMEO for
1125 more information.
1126
1127 listen_depth
1128 · Units: connections
1129
1130 · Default: 1024
1131
1132 · Minimum: 0
1133
1134 · Flags: must_restart
1135
1136 Listen queue depth.
1137
1138 lru_interval
1139 · Units: seconds
1140
1141 · Default: 2.000
1142
1143 · Minimum: 0.000
1144
1145 · Flags: experimental
1146
1147 Grace period before object moves on LRU list. Objects are only moved
1148 to the front of the LRU list if they have not been moved there already
1149 inside this timeout period. This reduces the amount of lock operations
1150 necessary for LRU list access.
1151
1152 max_esi_depth
1153 · Units: levels
1154
1155 · Default: 5
1156
1157 · Minimum: 0
1158
1159 Maximum depth of esi:include processing.
1160
1161 max_restarts
1162 · Units: restarts
1163
1164 · Default: 4
1165
1166 · Minimum: 0
1167
1168 Upper limit on how many times a request can restart.
1169
1170 max_retries
1171 · Units: retries
1172
1173 · Default: 4
1174
1175 · Minimum: 0
1176
1177 Upper limit on how many times a backend fetch can retry.
1178
1179 max_vcl
1180 · Default: 100
1181
1182 · Minimum: 0
1183
1184 Threshold of loaded VCL programs. (VCL labels are not counted.)
1185 Parameter max_vcl_handling determines behaviour.
1186
1187 max_vcl_handling
1188 · Default: 1
1189
1190 · Minimum: 0
1191
1192 · Maximum: 2
1193
1194 Behaviour when attempting to exceed max_vcl loaded VCL.
1195
1196 · 0 - Ignore max_vcl parameter.
1197
1198 · 1 - Issue warning.
1199
1200 · 2 - Refuse loading VCLs.
1201
1202 nuke_limit
1203 · Units: allocations
1204
1205 · Default: 50
1206
1207 · Minimum: 0
1208
1209 · Flags: experimental
1210
1211 Maximum number of objects we attempt to nuke in order to make space for
1212 a object body.
1213
1214 pcre_match_limit
1215 · Default: 10000
1216
1217 · Minimum: 1
1218
1219 The limit for the number of calls to the internal match() function in
1220 pcre_exec().
1221
1222 (See: PCRE_EXTRA_MATCH_LIMIT in pcre docs.)
1223
1224 This parameter limits how much CPU time regular expression matching can
1225 soak up.
1226
1227 pcre_match_limit_recursion
1228 · Default: 20
1229
1230 · Minimum: 1
1231
1232 The recursion depth-limit for the internal match() function in a
1233 pcre_exec().
1234
1235 (See: PCRE_EXTRA_MATCH_LIMIT_RECURSION in pcre docs.)
1236
1237 This puts an upper limit on the amount of stack used by PCRE for cer‐
1238 tain classes of regular expressions.
1239
1240 We have set the default value low in order to prevent crashes, at the
1241 cost of possible regexp matching failures.
1242
1243 Matching failures will show up in the log as VCL_Error messages with
1244 regexp errors -27 or -21.
1245
1246 Testcase r01576 can be useful when tuning this parameter.
1247
1248 ping_interval
1249 · Units: seconds
1250
1251 · Default: 3
1252
1253 · Minimum: 0
1254
1255 · Flags: must_restart
1256
1257 Interval between pings from parent to child. Zero will disable pinging
1258 entirely, which makes it possible to attach a debugger to the child.
1259
1260 pipe_sess_max
1261 · Units: connections
1262
1263 · Default: 0
1264
1265 · Minimum: 0
1266
1267 Maximum number of sessions dedicated to pipe transactions.
1268
1269 pipe_timeout
1270 · Units: seconds
1271
1272 · Default: 60.000
1273
1274 · Minimum: 0.000
1275
1276 Idle timeout for PIPE sessions. If nothing have been received in either
1277 direction for this many seconds, the session is closed.
1278
1279 pool_req
1280 · Default: 10,100,10
1281
1282 Parameters for per worker pool request memory pool.
1283
1284 The three numbers are:
1285
1286 min_pool
1287 minimum size of free pool.
1288
1289 max_pool
1290 maximum size of free pool.
1291
1292 max_age
1293 max age of free element.
1294
1295 pool_sess
1296 · Default: 10,100,10
1297
1298 Parameters for per worker pool session memory pool.
1299
1300 The three numbers are:
1301
1302 min_pool
1303 minimum size of free pool.
1304
1305 max_pool
1306 maximum size of free pool.
1307
1308 max_age
1309 max age of free element.
1310
1311 pool_vbo
1312 · Default: 10,100,10
1313
1314 Parameters for backend object fetch memory pool.
1315
1316 The three numbers are:
1317
1318 min_pool
1319 minimum size of free pool.
1320
1321 max_pool
1322 maximum size of free pool.
1323
1324 max_age
1325 max age of free element.
1326
1327 prefer_ipv6
1328 · Units: bool
1329
1330 · Default: off
1331
1332 Prefer IPv6 address when connecting to backends which have both IPv4
1333 and IPv6 addresses.
1334
1335 rush_exponent
1336 · Units: requests per request
1337
1338 · Default: 3
1339
1340 · Minimum: 2
1341
1342 · Flags: experimental
1343
1344 How many parked request we start for each completed request on the
1345 object. NB: Even with the implict delay of delivery, this parameter
1346 controls an exponential increase in number of worker threads.
1347
1348 send_timeout
1349 · Units: seconds
1350
1351 · Default: 600.000
1352
1353 · Minimum: 0.000
1354
1355 · Flags: delayed
1356
1357 Total timeout for ordinary HTTP1 responses. Does not apply to some
1358 internally generated errors and pipe mode.
1359
1360 When 'idle_send_timeout' is hit while sending an HTTP1 response, the
1361 timeout is extended unless the total time already taken for sending the
1362 response in its entirety exceeds this many seconds.
1363
1364 When this timeout is hit, the session is closed
1365
1366 shortlived
1367 · Units: seconds
1368
1369 · Default: 10.000
1370
1371 · Minimum: 0.000
1372
1373 Objects created with (ttl+grace+keep) shorter than this are always put
1374 in transient storage.
1375
1376 sigsegv_handler
1377 · Units: bool
1378
1379 · Default: on
1380
1381 · Flags: must_restart
1382
1383 Install a signal handler which tries to dump debug information on seg‐
1384 mentation faults, bus errors and abort signals.
1385
1386 syslog_cli_traffic
1387 · Units: bool
1388
1389 · Default: on
1390
1391 Log all CLI traffic to syslog(LOG_INFO).
1392
1393 tcp_fastopen
1394 · Units: bool
1395
1396 · Default: off
1397
1398 · Flags: must_restart
1399
1400 Enable TCP Fast Open extension.
1401
1402 tcp_keepalive_intvl
1403 · Units: seconds
1404
1405 · Default: platform dependent
1406
1407 · Minimum: 1.000
1408
1409 · Maximum: 100.000
1410
1411 · Flags: experimental
1412
1413 The number of seconds between TCP keep-alive probes. Ignored for Unix
1414 domain sockets.
1415
1416 tcp_keepalive_probes
1417 · Units: probes
1418
1419 · Default: platform dependent
1420
1421 · Minimum: 1
1422
1423 · Maximum: 100
1424
1425 · Flags: experimental
1426
1427 The maximum number of TCP keep-alive probes to send before giving up
1428 and killing the connection if no response is obtained from the other
1429 end. Ignored for Unix domain sockets.
1430
1431 tcp_keepalive_time
1432 · Units: seconds
1433
1434 · Default: platform dependent
1435
1436 · Minimum: 1.000
1437
1438 · Maximum: 7200.000
1439
1440 · Flags: experimental
1441
1442 The number of seconds a connection needs to be idle before TCP begins
1443 sending out keep-alive probes. Ignored for Unix domain sockets.
1444
1445 thread_pool_add_delay
1446 · Units: seconds
1447
1448 · Default: 0.000
1449
1450 · Minimum: 0.000
1451
1452 · Flags: experimental
1453
1454 Wait at least this long after creating a thread.
1455
1456 Some (buggy) systems may need a short (sub-second) delay between creat‐
1457 ing threads. Set this to a few milliseconds if you see the
1458 'threads_failed' counter grow too much.
1459
1460 Setting this too high results in insufficient worker threads.
1461
1462 thread_pool_destroy_delay
1463 · Units: seconds
1464
1465 · Default: 1.000
1466
1467 · Minimum: 0.010
1468
1469 · Flags: delayed, experimental
1470
1471 Wait this long after destroying a thread.
1472
1473 This controls the decay of thread pools when idle(-ish).
1474
1475 thread_pool_fail_delay
1476 · Units: seconds
1477
1478 · Default: 0.200
1479
1480 · Minimum: 0.010
1481
1482 · Flags: experimental
1483
1484 Wait at least this long after a failed thread creation before trying to
1485 create another thread.
1486
1487 Failure to create a worker thread is often a sign that the end is
1488 near, because the process is running out of some resource. This delay
1489 tries to not rush the end on needlessly.
1490
1491 If thread creation failures are a problem, check that thread_pool_max
1492 is not too high.
1493
1494 It may also help to increase thread_pool_timeout and thread_pool_min,
1495 to reduce the rate at which treads are destroyed and later recreated.
1496
1497 thread_pool_max
1498 · Units: threads
1499
1500 · Default: 5000
1501
1502 · Minimum: thread_pool_min
1503
1504 · Flags: delayed
1505
1506 The maximum number of worker threads in each pool.
1507
1508 Do not set this higher than you have to, since excess worker threads
1509 soak up RAM and CPU and generally just get in the way of getting work
1510 done.
1511
1512 thread_pool_min
1513 · Units: threads
1514
1515 · Default: 100
1516
1517 · Minimum: 5
1518
1519 · Maximum: thread_pool_max
1520
1521 · Flags: delayed
1522
1523 The minimum number of worker threads in each pool.
1524
1525 Increasing this may help ramp up faster from low load situations or
1526 when threads have expired.
1527
1528 Technical minimum is 5 threads, but this parameter is strongly recom‐
1529 mended to be at least 10
1530
1531 thread_pool_reserve
1532 · Units: threads
1533
1534 · Default: 0
1535
1536 · Maximum: 95% of thread_pool_min
1537
1538 · Flags: delayed
1539
1540 The number of worker threads reserved for vital tasks in each pool.
1541
1542 Tasks may require other tasks to complete (for example, client requests
1543 may require backend requests, http2 sessions require streams, which
1544 require requests). This reserve is to ensure that lower priority tasks
1545 do not prevent higher priority tasks from running even under high load.
1546
1547 The effective value is at least 5 (the number of internal priority
1548 classes), irrespective of this parameter. Default is 0 to auto-tune
1549 (5% of thread_pool_min). Minimum is 1 otherwise, maximum is 95% of
1550 thread_pool_min.
1551
1552 thread_pool_stack
1553 · Units: bytes
1554
1555 · Default: sysconf(_SC_THREAD_STACK_MIN)
1556
1557 · Minimum: 16k
1558
1559 · Flags: delayed
1560
1561 Worker thread stack size. This will likely be rounded up to a multiple
1562 of 4k (or whatever the page_size might be) by the kernel.
1563
1564 The required stack size is primarily driven by the depth of the
1565 call-tree. The most common relevant determining factors in varnish core
1566 code are GZIP (un)compression, ESI processing and regular expression
1567 matches. VMODs may also require significant amounts of additional
1568 stack. The nesting depth of VCL subs is another factor, although typi‐
1569 cally not predominant.
1570
1571 The stack size is per thread, so the maximum total memory required for
1572 worker thread stacks is in the order of size = thread_pools x
1573 thread_pool_max x thread_pool_stack.
1574
1575 Thus, in particular for setups with many threads, keeping the stack
1576 size at a minimum helps reduce the amount of memory required by Var‐
1577 nish.
1578
1579 On the other hand, thread_pool_stack must be large enough under all
1580 circumstances, otherwise varnish will crash due to a stack overflow.
1581 Usually, a stack overflow manifests itself as a segmentation fault (aka
1582 segfault / SIGSEGV) with the faulting address being near the stack
1583 pointer (sp).
1584
1585 Unless stack usage can be reduced, thread_pool_stack must be increased
1586 when a stack overflow occurs. Setting it in 150%-200% increments is
1587 recommended until stack overflows cease to occur.
1588
1589 thread_pool_timeout
1590 · Units: seconds
1591
1592 · Default: 300.000
1593
1594 · Minimum: 10.000
1595
1596 · Flags: delayed, experimental
1597
1598 Thread idle threshold.
1599
1600 Threads in excess of thread_pool_min, which have been idle for at least
1601 this long, will be destroyed.
1602
1603 thread_pool_watchdog
1604 · Units: seconds
1605
1606 · Default: 60.000
1607
1608 · Minimum: 0.100
1609
1610 · Flags: experimental
1611
1612 Thread queue stuck watchdog.
1613
1614 If no queued work have been released for this long, the worker process
1615 panics itself.
1616
1617 thread_pools
1618 · Units: pools
1619
1620 · Default: 2
1621
1622 · Minimum: 1
1623
1624 · Maximum: defined when Varnish is built
1625
1626 · Flags: delayed, experimental
1627
1628 Number of worker thread pools.
1629
1630 Increasing the number of worker pools decreases lock contention. Each
1631 worker pool also has a thread accepting new connections, so for very
1632 high rates of incoming new connections on systems with many cores,
1633 increasing the worker pools may be required.
1634
1635 Too many pools waste CPU and RAM resources, and more than one pool for
1636 each CPU is most likely detrimental to performance.
1637
1638 Can be increased on the fly, but decreases require a restart to take
1639 effect.
1640
1641 thread_queue_limit
1642 · Default: 20
1643
1644 · Minimum: 0
1645
1646 · Flags: experimental
1647
1648 Permitted request queue length per thread-pool.
1649
1650 This sets the number of requests we will queue, waiting for an avail‐
1651 able thread. Above this limit sessions will be dropped instead of
1652 queued.
1653
1654 thread_stats_rate
1655 · Units: requests
1656
1657 · Default: 10
1658
1659 · Minimum: 0
1660
1661 · Flags: experimental
1662
1663 Worker threads accumulate statistics, and dump these into the global
1664 stats counters if the lock is free when they finish a job
1665 (request/fetch etc.) This parameters defines the maximum number of
1666 jobs a worker thread may handle, before it is forced to dump its accu‐
1667 mulated stats into the global counters.
1668
1669 timeout_idle
1670 · Units: seconds
1671
1672 · Default: 5.000
1673
1674 · Minimum: 0.000
1675
1676 Idle timeout for client connections.
1677
1678 A connection is considered idle until we have received the full request
1679 headers.
1680
1681 This parameter is particularly relevant for HTTP1 keepalive connec‐
1682 tions which are closed unless the next request is received before this
1683 timeout is reached.
1684
1685 timeout_linger
1686 · Units: seconds
1687
1688 · Default: 0.050
1689
1690 · Minimum: 0.000
1691
1692 · Flags: experimental
1693
1694 How long the worker thread lingers on an idle session before handing it
1695 over to the waiter. When sessions are reused, as much as half of all
1696 reuses happen within the first 100 msec of the previous request com‐
1697 pleting. Setting this too high results in worker threads not doing
1698 anything for their keep, setting it too low just means that more ses‐
1699 sions take a detour around the waiter.
1700
1701 vcc_allow_inline_c
1702 · Units: bool
1703
1704 · Default: off
1705
1706 Allow inline C code in VCL.
1707
1708 vcc_err_unref
1709 · Units: bool
1710
1711 · Default: on
1712
1713 Unreferenced VCL objects result in error.
1714
1715 vcc_unsafe_path
1716 · Units: bool
1717
1718 · Default: on
1719
1720 Allow '/' in vmod & include paths. Allow 'import ... from ...'.
1721
1722 vcl_cooldown
1723 · Units: seconds
1724
1725 · Default: 600.000
1726
1727 · Minimum: 1.000
1728
1729 How long a VCL is kept warm after being replaced as the active VCL
1730 (granularity approximately 30 seconds).
1731
1732 vcl_path
1733 · Default: /usr/local/etc/varnish:/usr/local/share/varnish/vcl
1734
1735 Directory (or colon separated list of directories) from which relative
1736 VCL filenames (vcl.load and include) are to be found. By default Var‐
1737 nish searches VCL files in both the system configuration and shared
1738 data directories to allow packages to drop their VCL files in a stan‐
1739 dard location where relative includes would work.
1740
1741 vmod_path
1742 · Default: /usr/local/lib/varnish/vmods
1743
1744 Directory (or colon separated list of directories) where VMODs are to
1745 be found.
1746
1747 vsl_buffer
1748 · Units: bytes
1749
1750 · Default: 4k
1751
1752 · Minimum: vsl_reclen + 12 bytes
1753
1754 Bytes of (req-/backend-)workspace dedicated to buffering VSL records.
1755 When this parameter is adjusted, most likely workspace_client and
1756 workspace_backend will have to be adjusted by the same amount.
1757
1758 Setting this too high costs memory, setting it too low will cause more
1759 VSL flushes and likely increase lock-contention on the VSL mutex.
1760
1761 vsl_mask
1762 · Default: -Debug,-ObjProtocol,-ObjStatus,-ObjReason,-Obj‐
1763 Header,-VCL_trace,-Work‐
1764 Thread,-Hash,-VfpAcct,-H2RxHdr,-H2RxBody,-H2TxHdr,-H2TxBody
1765
1766 Mask individual VSL messages from being logged.
1767
1768 default
1769 Set default value
1770
1771 Use +/- prefix in front of VSL tag name to unmask/mask individual VSL
1772 messages.
1773
1774 vsl_reclen
1775 · Units: bytes
1776
1777 · Default: 255b
1778
1779 · Minimum: 16b
1780
1781 · Maximum: vsl_buffer - 12 bytes
1782
1783 Maximum number of bytes in SHM log record.
1784
1785 vsl_space
1786 · Units: bytes
1787
1788 · Default: 80M
1789
1790 · Minimum: 1M
1791
1792 · Maximum: 4G
1793
1794 · Flags: must_restart
1795
1796 The amount of space to allocate for the VSL fifo buffer in the VSM mem‐
1797 ory segment. If you make this too small, varnish{ncsa|log} etc will
1798 not be able to keep up. Making it too large just costs memory
1799 resources.
1800
1801 vsm_free_cooldown
1802 · Units: seconds
1803
1804 · Default: 60.000
1805
1806 · Minimum: 10.000
1807
1808 · Maximum: 600.000
1809
1810 How long VSM memory is kept warm after a deallocation (granularity
1811 approximately 2 seconds).
1812
1813 vsm_space
1814 · Units: bytes
1815
1816 · Default: 1M
1817
1818 · Minimum: 1M
1819
1820 · Maximum: 1G
1821
1822 DEPRECATED: This parameter is ignored. There is no global limit on
1823 amount of shared memory now.
1824
1825 workspace_backend
1826 · Units: bytes
1827
1828 · Default: 64k
1829
1830 · Minimum: 1k
1831
1832 · Flags: delayed
1833
1834 Bytes of HTTP protocol workspace for backend HTTP req/resp. If larger
1835 than 4k, use a multiple of 4k for VM efficiency.
1836
1837 workspace_client
1838 · Units: bytes
1839
1840 · Default: 64k
1841
1842 · Minimum: 9k
1843
1844 · Flags: delayed
1845
1846 Bytes of HTTP protocol workspace for clients HTTP req/resp. Use a mul‐
1847 tiple of 4k for VM efficiency. For HTTP/2 compliance this must be at
1848 least 20k, in order to receive fullsize (=16k) frames from the client.
1849 That usually happens only in POST/PUT bodies. For other traffic-pat‐
1850 terns smaller values work just fine.
1851
1852 workspace_session
1853 · Units: bytes
1854
1855 · Default: 0.75k
1856
1857 · Minimum: 0.25k
1858
1859 · Flags: delayed
1860
1861 Allocation size for session structure and workspace. The workspace
1862 is primarily used for TCP connection addresses. If larger than 4k, use
1863 a multiple of 4k for VM efficiency.
1864
1865 workspace_thread
1866 · Units: bytes
1867
1868 · Default: 2k
1869
1870 · Minimum: 0.25k
1871
1872 · Maximum: 8k
1873
1874 · Flags: delayed
1875
1876 Bytes of auxiliary workspace per thread. This workspace is used for
1877 certain temporary data structures during the operation of a worker
1878 thread. One use is for the IO-vectors used during delivery. Setting
1879 this parameter too low may increase the number of writev() syscalls,
1880 setting it too high just wastes space. ~0.1k + UIO_MAXIOV *
1881 sizeof(struct iovec) (typically = ~16k for 64bit) is considered the
1882 maximum sensible value under any known circumstances (excluding exotic
1883 vmod use).
1884
1886 Varnish and bundled tools will, in most cases, exit with one of the
1887 following codes
1888
1889 · 0 OK
1890
1891 · 1 Some error which could be system-dependent and/or transient
1892
1893 · 2 Serious configuration / parameter error - retrying with the same
1894 configuration / parameters is most likely useless
1895
1896 The varnishd master process may also OR its exit code
1897
1898 · with 0x20 when the varnishd child process died,
1899
1900 · with 0x40 when the varnishd child process was terminated by a signal
1901 and
1902
1903 · with 0x80 when a core was dumped.
1904
1906 · varnishlog(1)
1907
1908 · varnishhist(1)
1909
1910 · varnishncsa(1)
1911
1912 · varnishstat(1)
1913
1914 · varnishtop(1)
1915
1916 · varnish-cli(7)
1917
1918 · vcl(7)
1919
1921 The varnishd daemon was developed by Poul-Henning Kamp in cooperation
1922 with Verdens Gang AS and Varnish Software.
1923
1924 This manual page was written by Dag-Erling Smørgrav with updates by
1925 Stig Sandbeck Mathisen <ssm@debian.org>, Nils Goroll and others.
1926
1928 This document is licensed under the same licence as Varnish itself. See
1929 LICENCE for details.
1930
1931 · Copyright (c) 2007-2015 Varnish Software AS
1932
1933
1934
1935
1936 VARNISHD(1)