1MEMASLAP(1) libmemcached-awesome MEMASLAP(1)
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6 memaslap - libmemcached Documentation
7
9 memaslap [options]
10 --help
12 MEMCACHED_SERVERS
14
16 memaslap is a load generation and benchmark tool for memcached servers.
17 It generates configurable workload such as threads, concurrency, con‐
18 nections, run time, overwrite, miss rate, key size, value size, get/set
19 proportion, expected throughput, and so on. Furthermore, it also tests
20 data verification, expire-time verification, UDP, binary protocol,
21 facebook test, replication test, multi-get and reconnection, etc.
22 Memaslap manages network connections like memcached with libevent. Each
24 thread of memaslap is bound with a CPU core, all the threads don't com‐
25 municate with each other, and there are several socket connections in
26 each thread. Each connection keeps key size distribution, value size
27 distribution, and command distribution by itself.
28 You can specify servers via the memslap --servers option or via the en‐
30 vironment variable MEMCACHED_SERVERS.
31
33 Memslap is developed to for the following purposes:
34 Manages network connections with libevent asynchronously.
36 Set both TCP and UDP up to use non-blocking IO.
38 Improves parallelism: higher performance in multi-threads environments.
40 Improves time efficiency: faster processing speed.
42 Generates key and value more efficiently; key size distribution and
44 value size distribution are configurable.
45 Supports get, multi-get, and set commands; command distribution is con‐
47 figurable.
48 Supports controllable miss rate and overwrite rate.
50 Supports data and expire-time verification.
52 Supports dumping statistic information periodically.
54 Supports thousands of TCP connections.
56 Supports binary protocol.
58 Supports facebook test (set with TCP and multi-get with UDP) and repli‐
60 cation test.
61
63 Effective implementation of network.
64 For memaslap, both TCP and UDP use non-blocking network IO. All the
65 network events are managed by libevent as memcached. The network module
66 of memaslap is similar to memcached. Libevent can ensure memaslap can
67 handle network very efficiently.
68 Effective implementation of multi-threads and concurrency
70 Memslap has the similar implementation of multi-threads to memcached.
71 Memslap creates one or more self-governed threads; each thread is bound
72 with one CPU core if the system tests setting CPU core affinity.
73 In addition, each thread has a libevent to manage the events of the
75 network; each thread has one or more self-governed concurrency; and
76 each concurrency has one or more socket connections. All the concurrent
77 tasks don't communicate with each other even though they are in the
78 same thread.
79 Memslap can create thousands of socket connections, and each concur‐
81 rency has tens of socket connections. Each concurrency randomly or se‐
82 quentially selects one socket connection from its socket connection
83 pool to run, so memaslap can ensure each concurrency handles one socket
84 connection at any given time. Users can specify the number of concur‐
85 rency and socket connections of each concurrency according to their ex‐
86 pected workload.
87 Effective implementation of generating key and value
89 In order to improve time efficiency and space efficiency, memaslap cre‐
90 ates a random characters table with 10M characters. All the suffixes of
91 keys and values are generated from this random characters table.
92 Memslap uses the offset in the character table and the length of the
94 string to identify a string. It can save much memory. Each key con‐
95 tains two parts, a prefix and a suffix. The prefix is an uint64_t, 8
96 bytes. In order to verify the data set before, memaslap need to ensure
97 each key is unique, so it uses the prefix to identify a key. The prefix
98 cannot include illegal characters, such as 'r', 'n', '0' and ' '. And
99 memaslap has an algorithm to ensure that.
100 Memslap doesn't generate all the objects (key-value pairs) at the be‐
102 ginning. It only generates enough objects to fill the task window (de‐
103 fault 10K objects) of each concurrency. Each object has the following
104 basic information, key prefix, key suffix offset in the character ta‐
105 ble, key length, value offset in the character table, and value length.
106 In the work process, each concurrency sequentially or randomly selects
108 an object from the window to do set operation or get operation. At the
109 same time, each concurrency kicks objects out of its window and adds
110 new object into it.
111 Simple but useful task scheduling
113 Memslap uses libevent to schedule all concurrent tasks of threads, and
114 each concurrency schedules tasks based on the local task window. Mem‐
115 slap assumes that if each concurrency keeps the same key distribution,
116 value distribution and commands distribution, from outside, memaslap
117 keeps all the distribution as a whole. Each task window includes a lot
118 of objects, each object stores its basic information, such as key,
119 value, expire time, and so on. At any time, all the objects in the win‐
120 dow keep the same and fixed key and value distribution. If an object is
121 overwritten, the value of the object will be updated. Memslap verifies
122 the data or expire-time according to the object information stored in
123 the task window.
124 Libevent selects which concurrency to handle based on a specific net‐
126 work event. Then the concurrency selects which command (get or set) to
127 operate based on the command distribution. If it needs to kick out an
128 old object and add a new object, in order to keep the same key and
129 value distribution, the new object must have the same key length and
130 value length.
131 If memcached server has two cache layers (memory and SSD), running
133 memaslap with different window sizes can get different cache miss
134 rates. If memaslap adds enough objects into the windows at the begin‐
135 ning, and the cache of memcached cannot store all the objects initial‐
136 ized, then memaslap will get some objects from the second cache layer.
137 It causes the first cache layer to miss. So the user can specify the
138 window size to get the expected miss rate of the first cache layer.
139 Useful implementation of multi-servers , UDP, TCP, multi-get and binary
141 protocol
142 Because each thread is self-governed, memaslap can assign different
143 threads to handle different memcached servers. This is just one of the
144 ways in which memaslap tests multiple servers. The only limitation is
145 that the number of servers cannot be greater than the number of
146 threads. The other way to test multiple servers is for replication
147 test. Each concurrency has one socket connection to each memcached
148 server. For the implementation, memaslap can set some objects to one
149 memcached server, and get these objects from the other servers.
150 By default, Memslap does single get. If the user specifies multi-get
152 option, memaslap will collect enough get commands and pack and send the
153 commands together.
154 Memslap tests both the ASCII protocol and binary protocol, but it runs
156 on the ASCII protocol by default. Memslap by default runs on the TCP
157 protocol, but it also tests UDP. Because UDP is unreliable, dropped
158 packages and out-of-order packages may occur. Memslap creates a memory
159 buffer to handle these problems. Memslap tries to read all the response
160 data of one command from the server and reorders the response data. If
161 some packages get lost, the waiting timeout mechanism can ensure
162 half-baked packages will be discarded and the next command will be
163 sent.
164
166 Below are some usage samples:
167 memaslap -s 127.0.0.1:11211 -S 5s
169 memaslap -s 127.0.0.1:11211 -t 2m -v 0.2 -e 0.05 -b
171 memaslap -s 127.0.0.1:11211 -F config -t 2m -w 40k -S 20s -o 0.2
173 memaslap -s 127.0.0.1:11211 -F config -t 2m -T 4 -c 128 -d 20 -P 40k
175 memaslap -s 127.0.0.1:11211 -F config -t 2m -d 50 -a -n 40
177 memaslap -s 127.0.0.1:11211,127.0.0.1:11212 -F config -t 2m
179 memaslap -s 127.0.0.1:11211,127.0.0.1:11212 -F config -t 2m -p 2
181 The user must specify one server at least to run memaslap. The rest of
183 the parameters have default values, as shown below:
184 Thread number = 1 Concurrency = 16
186 Run time = 600 seconds Configuration file = NULL
188 Key size = 64 Value size = 1024
190 Get/set = 9:1 Window size = 10k
192 Execute number = 0 Single get = true
194 Multi-get = false Number of sockets of each concur‐
196 rency = 1
197 Reconnect = false Data verification = false
199 Expire-time verification = false ASCII protocol = true
201 Binary protocol = false Dumping statistic information pe‐
203 riodically = false
204 Overwrite proportion = 0% UDP = false
206 TCP = true Limit throughput = false
208 Facebook test = false Replication test = false
210 Key size, value size and command distribution.
212 All the distributions are read from the configuration file specified by
213 user with "—cfg_cmd" option. If the user does not specify a configura‐
214 tion file, memaslap will run with the default distribution (key size =
215 64, value size = 1024, get/set = 9:1). For information on how to edit
216 the configuration file, refer to the "Configuration File" section.
217 The minimum key size is 16 bytes; the maximum key size is 250 bytes.
219 The precision of proportion is 0.001. The proportion of distribution
220 will be rounded to 3 decimal places.
221 The minimum value size is 1 bytes; the maximum value size is 1M bytes.
223 The precision of proportion is 0.001. The proportion of distribution
224 will be rounded to 3 decimal places. Currently, memaslap only tests
225 set and get commands. And it testss 100% set and 100% get. For 100%
226 get, it will preset some objects to the server.
227 Multi-thread and concurrency
229 The high performance of memaslap benefits from the special schedule of
230 thread and concurrency. It's important to specify the proper number of
231 them. The default number of threads is 1; the default number of concur‐
232 rency is 16. The user can use "—threads" and "--concurrency" to specify
233 these variables.
234 If the system tests setting CPU affinity and the number of threads
236 specified by the user is greater than 1, memaslap will try to bind each
237 thread to a different CPU core. So if you want to get the best perfor‐
238 mance memaslap, it is better to specify the number of thread equal to
239 the number of CPU cores. The number of threads specified by the user
240 can also be less or greater than the number of CPU cores. Because of
241 the limitation of implementation, the number of concurrencies could be
242 the multiple of the number of threads.
243 1. For 8 CPU cores system
245 For example:
247 --threads=2 --concurrency=128
249 --threads=8 --concurrency=128
251 --threads=8 --concurrency=256
253 --threads=12 --concurrency=144
255 2. For 16 CPU cores system
257 For example:
259 --threads=8 --concurrency=128
261 --threads=16 --concurrency=256
263 --threads=16 --concurrency=512
265 --threads=24 --concurrency=288
267 The memaslap performs very well, when used to test the performance of
269 memcached servers. Most of the time, the bottleneck is the network or
270 the server. If for some reason the user wants to limit the performance
271 of memaslap, there are two ways to do this:
272 Decrease the number of threads and concurrencies. Use the option
274 "--tps" that memaslap provides to limit the throughput. This option al‐
275 lows the user to get the expected throughput. For example, assume that
276 the maximum throughput is 50 kops/s for a specific configuration, you
277 can specify the throughput equal to or less than the maximum throughput
278 using "--tps" option.
279 Window size
281 Most of the time, the user does not need to specify the window size.
282 The default window size is 10k. For Schooner Memcached, the user can
283 specify different window sizes to get different cache miss rates based
284 on the test case. Memslap testss cache miss rate between 0% and 100%.
285 If you use this utility to test the performance of Schooner Memcached,
286 you can specify a proper window size to get the expected cache miss
287 rate. The formula for calculating window size is as follows:
288 Assume that the key size is 128 bytes, and the value size is 2048
290 bytes, and concurrency=128.
291 1. Small cache cache_size=1M, 100% cache miss (all data get from SSD).
293 win_size=10k
294 2. cache_size=4G
296 (1). cache miss rate 0%
298 win_size=8k
300 (2). cache miss rate 5%
302 win_size=11k
304 3. cache_size=16G
306 (1). cache miss rate 0%
308 win_size=32k
310 (2). cache miss
312 rate 5%
314 win_size=46k
316 The formula for calculating window size for cache miss rate 0%:
318 cache_size / concurrency / (key_size + value_size) * 0.5
320 The formula for calculating window size for cache miss rate 5%:
322 cache_size / concurrency / (key_size + value_size) * 0.7
324 Verification
326 Memslap testss both data verification and expire-time verification. The
327 user can use "--verify=" or "-v" to specify the proportion of data ver‐
328 ification. In theory, it testss 100% data verification. The user can
329 use "--exp_verify=" or "-e" to specify the proportion of expire-time
330 verification. In theory, it testss 100% expire-time verification. Spec‐
331 ify the "--verbose" options to get more detailed error information.
332 For example: --exp_verify=0.01 –verify=0.1 , it means that 1% of the
334 objects set with expire-time, 10% of the objects gotten will be veri‐
335 fied. If the objects are gotten, memaslap will verify the expire-time
336 and value.
337 multi-servers and multi-config
339 Memslap testss multi-servers based on self-governed thread. There is a
340 limitation that the number of servers cannot be greater than the number
341 of threads. Memslap assigns one thread to handle one server at least.
342 The user can use the "--servers=" or "-s" option to specify
343 multi-servers.
344 For example:
346 --servers=10.1.1.1:11211,10.1.1.2:11212,10.1.1.3:11213 --threads=6
348 --concurrency=36
349 The above command means that there are 6 threads, with each thread hav‐
351 ing 6 concurrencies and that threads 0 and 3 handle server 0
352 (10.1.1.1); threads 1 and 4 handle server 1 (10.1.1.2); and thread 2
353 and 5 handle server 2 (10.1.1.3).
354 All the threads and concurrencies in memaslap are self-governed.
356 So is memaslap. The user can start up several memaslap instances. The
358 user can run memaslap on different client machines to communicate with
359 the same memcached server at the same. It is recommended that the user
360 start different memaslap on different machines using the same configu‐
361 ration.
362 Run with execute number mode or time mode
364 The default memaslap runs with time mode. The default run time is 10
365 minutes. If it times out, memaslap will exit. Do not specify both exe‐
366 cute number mode and time mode at the same time; just specify one in‐
367 stead.
368 For example:
370 --time=30s (It means the test will run 30 seconds.)
372 --execute_number=100000 (It means that after running 100000 commands,
374 the test will exit.)
375 Dump statistic information periodically.
377 The user can use "--stat_freq=" or "-S" to specify the frequency.
378 For example:
380 --stat_freq=20s
382 Memslap will dump the statistics of the commands (get and set) at the
384 frequency of every 20 seconds.
385 For more information on the format of dumping statistic information,
387 refer to "Format of Output" section.
388 Multi-get
390 The user can use "--division=" or "-d" to specify multi-get keys count.
391 Memslap by default does single get with TCP. Memslap also testss data
392 verification and expire-time verification for multi-get.
393 Memslap testss multi-get with both TCP and UDP. Because of the differ‐
395 ent implementation of the ASCII protocol and binary protocol, there are
396 some differences between the two. For the ASCII protocol, memaslap
397 sends one "multi-get" to the server once. For the binary protocol,
398 memaslap sends several single get commands together as "multi-get" to
399 the server.
400 UDP and TCP
402 Memslap testss both UDP and TCP. For TCP, memaslap does not reconnect
403 the memcached server if socket connections are lost. If all the socket
404 connections are lost or memcached server crashes, memaslap will exit.
405 If the user specifies the "--reconnect" option when socket connections
406 are lost, it will reconnect them.
407 User can use "--udp" to enable the UDP feature, but UDP comes with some
409 limitations:
410 UDP cannot set data more than 1400 bytes.
412 UDP is not tested by the binary protocol because the binary protocol of
414 memcached does not tests that.
415 UDP doesn't tests reconnection.
417 Facebook test
419 Set data with TCP and multi-get with UDP. Specify the following op‐
420 tions:
421 "--facebook --division=50"
423 If you want to create thousands of TCP connections, specify the
425 "--conn_sock=" option.
427 For example: --facebook --division=50 --conn_sock=200
429 The above command means that memaslap will do facebook test, each con‐
431 currency has 200 socket TCP connections and one UDP socket.
432 Memslap sets objects with the TCP socket, and multi-gets 50 objects
434 once with the UDP socket.
435 If you specify "--division=50", the key size must be less that 25 bytes
437 because the UDP packet size is 1400 bytes.
438 Replication test
440 For replication test, the user must specify at least two memcached
441 servers. The user can use "—rep_write=" option to enable feature.
442 For example:
444 --servers=10.1.1.1:11211,10.1.1.2:11212 –rep_write=2
446 The above command means that there are 2 replication memcached servers,
448 memaslap will set objects to both server 0 and server 1, get objects
449 which are set to server 0 before from server 1, and also get objects
450 which are set to server 1 before from server 0. If server 0 crashes,
451 memaslap will only get objects from server 1. If server 0 comes back to
452 life again, memaslap will reconnect server 0. If both server 0 and
453 server 1 crash, memaslap will exit.
454 Supports thousands of TCP connections
456 Start memaslap with "--conn_sock=" or "-n" to enable this feature. Make
457 sure that your system can tests opening thousands of files and creating
458 thousands of sockets. However, this feature does not tests reconnection
459 if sockets disconnect.
460 For example:
462 --threads=8 --concurrency=128 --conn_sock=128
464 The above command means that memaslap starts up 8 threads, each thread
466 has 16 concurrencies, each concurrency has 128 TCP socket connections,
467 and the total number of TCP socket connections is 128 * 128 = 16384.
468 Supports binary protocol
470 Start memaslap with "--binary" or "-B" options to enable this feature.
471 It testss all the above features except UDP, because the latest mem‐
472 cached 1.3.3 does not implement binary UDP protocol.
473 For example:
475 --binary
477 Since memcached 1.3.3 doesn't implement binary UDP protocol, memaslap
479 does not tests UDP. In addition, memcached 1.3.3 does not tests
480 multi-get. If you specify "--division=50" option, it just sends 50 get
481 commands together as "multi-get" to the server.
482
484 This section describes the format of the configuration file. By de‐
485 fault when no configuration file is specified memaslap reads the de‐
486 fault one located at ~/.memaslap.cnf.
487 Below is a sample configuration file:
489 ---------------------------------------------------------------------------
491 #comments should start with '#'
492 #key
493 #start_len end_len proportion
494 #
495 #key length range from start_len to end_len
496 #start_len must be equal to or greater than 16
497 #end_len must be equal to or less than 250
498 #start_len must be equal to or greater than end_len
499 #memaslap will generate keys according to the key range
500 #proportion: indicates keys generated from one range accounts for the total
501 generated keys
502 #
503 #example1: key range 16~100 accounts for 80%
504 # key range 101~200 accounts for 10%
505 # key range 201~250 accounts for 10%
506 # total should be 1 (0.8+0.1+0.1 = 1)
507 #
508 # 16 100 0.8
509 # 101 200 0.1
510 # 201 249 0.1
511 #
512 #example2: all keys length are 128 bytes
513 #
514 # 128 128 1
515 key
516 128 128 1
517 #value
518 #start_len end_len proportion
519 #
520 #value length range from start_len to end_len
521 #start_len must be equal to or greater than 1
522 #end_len must be equal to or less than 1M
523 #start_len must be equal to or greater than end_len
524 #memaslap will generate values according to the value range
525 #proportion: indicates values generated from one range accounts for the
526 total generated values
527 #
528 #example1: value range 1~1000 accounts for 80%
529 # value range 1001~10000 accounts for 10%
530 # value range 10001~100000 accounts for 10%
531 # total should be 1 (0.8+0.1+0.1 = 1)
532 #
533 # 1 1000 0.8
534 # 1001 10000 0.1
535 # 10001 100000 0.1
536 #
537 #example2: all value length are 128 bytes
538 #
539 # 128 128 1
540 value
541 2048 2048 1
542 #cmd
543 #cmd_type cmd_proportion
544 #
545 #currently memaslap only testss get and set command.
546 #
547 #cmd_type
548 #set 0
549 #get 1
550 #
551 #example: set command accounts for 50%
552 # get command accounts for 50%
553 # total should be 1 (0.5+0.5 = 1)
554 #
555 # cmd
556 # 0 0.5
557 # 1 0.5
558 cmd
559 0 0.1
560 1.0 0.9
561
563 At the beginning, memaslap displays some configuration information as
564 follows:
565 servers : 127.0.0.1:11211
567 threads count: 1
569 concurrency: 16
571 run time: 20s
573 windows size: 10k
575 set proportion: set_prop=0.10
577 get proportion: get_prop=0.90
579 Where
581 servers : "servers"
582 The servers used by memaslap.
583 threads count
585 The number of threads memaslap runs with.
586 concurrency
588 The number of concurrencies memaslap runs with.
589 run time
591 How long to run memaslap.
592 windows size
594 The task window size of each concurrency.
595 set proportion
597 The proportion of set command.
598 get proportion
600 The proportion of get command.
601 The output of dynamic statistics is something like this:
603 ---------------------------------------------------------------------------------------------------------------------------------
605 Get Statistics
606 Type Time(s) Ops TPS(ops/s) Net(M/s) Get_miss Min(us) Max(us)
607 Avg(us) Std_dev Geo_dist
608 Period 5 345826 69165 65.3 0 27 2198 203
609 95.43 177.29
610 Global 20 1257935 62896 71.8 0 26 3791 224
611 117.79 192.60
612 Set Statistics
613 Type Time(s) Ops TPS(ops/s) Net(M/s) Get_miss Min(us) Max(us)
615 Avg(us) Std_dev Geo_dist
616 Period 5 38425 7685 7.3 0 42 628 240
617 88.05 220.21
618 Global 20 139780 6989 8.0 0 37 3790 253
619 117.93 224.83
620 Total Statistics
621 Type Time(s) Ops TPS(ops/s) Net(M/s) Get_miss Min(us) Max(us)
623 Avg(us) Std_dev Geo_dist
624 Period 5 384252 76850 72.5 0 27 2198 207
625 94.72 181.18
626 Global 20 1397720 69886 79.7 0 26 3791 227
627 117.93 195.60
628 ---------------------------------------------------------------------------------------------------------------------------------
629 Where
631 Get Statistics
632 Statistics information of get command
633 Set Statistics
635 Statistics information of set command
636 Total Statistics
638 Statistics information of both get and set command
639 Period
641 Result within a period
642 Global
644 Accumulated results
645 Ops
647 Total operations
648 TPS
650 Throughput, operations/second
651 Net
653 The rate of network
654 Get_miss
656 How many objects can't be gotten
657 Min
659 The minimum response time
660 Max
662 The maximum response time
663 Avg:
665 The average response time
666 Std_dev
668 Standard deviation of response time
669 Geo_dist
671 Geometric distribution based on natural exponential function
672 At the end, memaslap will output something like this:
674 ---------------------------------------------------------------------------------------------------------------------------------
676 Get Statistics (1257956 events)
677 Min: 26
678 Max: 3791
679 Avg: 224
680 Geo: 192.60
681 Std: 116.23
682 Log2 Dist:
683 4: 0 10 84490 215345
684 8: 484890 459823 12543 824
685 12: 31
686 Set Statistics (139782 events)
688 Min: 37
689 Max: 3790
690 Avg: 253
691 Geo: 224.84
692 Std: 116.83
693 Log2 Dist:
694 4: 0 0 4200 16988
695 8: 50784 65574 2064 167
696 12: 5
697 Total Statistics (1397738 events)
699 Min: 26
700 Max: 3791
701 Avg: 227
702 Geo: 195.60
703 Std: 116.60
704 Log2 Dist:
705 4: 0 10 88690 232333
706 8: 535674 525397 14607 991
707 12: 36
708 cmd_get: 1257969
710 cmd_set: 139785
711 get_misses: 0
712 verify_misses: 0
713 verify_failed: 0
714 expired_get: 0
715 unexpired_unget: 0
716 written_bytes: 242516030
717 read_bytes: 1003702556
718 object_bytes: 152086080
719 packet_disorder: 0
720 packet_drop: 0
721 udp_timeout: 0
722 Run time: 20.0s Ops: 1397754 TPS: 69817 Net_rate: 59.4M/s
724 ---------------------------------------------------------------------------------------------------------------------------------
725 Where
727 Get Statistics
728 Get statistics of response time
729 Set Statistics
731 Set statistics of response time
732 Total Statistics
734 Both get and set statistics of response time
735 Min
737 The accumulated and minimum response time
738 Max
740 The accumulated and maximum response time
741 Avg
743 The accumulated and average response time
744 Std
746 Standard deviation of response time
747 Log2 Dist
749 Geometric distribution based on logarithm 2
750 cmd_get
752 Total get commands done
753 cmd_set
755 Total set commands done
756 get_misses
758 How many objects can't be gotten from server
759 verify_misses
761 How many objects need to verify but can't get them
762 verify_failed
764 How many objects with insistent value
765 expired_get
767 How many objects are expired but we get them
768 unexpired_unget
770 How many objects are unexpired but we can't get them
771 written_bytes
773 Total written bytes
774 read_bytes
776 Total read bytes
777 object_bytes
779 Total object bytes
780 packet_disorder
782 How many UDP packages are disorder
783 packet_drop
785 How many UDP packages are lost
786 udp_timeout
788 How many times UDP time out happen
789 Run time
791 Total run time
792 Ops
794 Total operations
795 TPS
797 Throughput, operations/second
798 Net_rate
800 The average rate of network
801
803 -s, --servers=
804 List one or more servers to connect. Servers count must be less
805 than threads count. e.g.: --servers=localhost:1234,local‐
806 host:11211
807 -T, --threads=
809 Number of threads to startup, better equal to CPU numbers. De‐
810 fault 8.
811 -c, --concurrency=
813 Number of concurrency to simulate with load. Default 128.
814 -n, --conn_sock=
816 Number of TCP socks per concurrency. Default 1.
817 -x, --execute_number=
819 Number of operations(get and set) to execute for the given test.
820 Default 1000000.
821 -t, --time=
823 How long the test to run, suffix: s-seconds, m-minutes, h-hours,
824 d-days e.g.: --time=2h.
825 -F, --cfg_cmd=
827 Load the configure file to get command,key and value distribu‐
828 tion list.
829 -w, --win_size=
831 Task window size of each concurrency, suffix: K, M e.g.:
832 --win_size=10k. Default 10k.
833 -X, --fixed_size=
835 Fixed length of value.
836 -v, --verify=
838 The proportion of date verification, e.g.: --verify=0.01
839 -d, --division=
841 Number of keys to multi-get once. Default 1, means single get.
842 -S, --stat_freq=
844 Frequency of dumping statistic information. suffix: s-seconds,
845 m-minutes, e.g.: --resp_freq=10s.
846 -e, --exp_verify=
848 The proportion of objects with expire time, e.g.: --exp_ver‐
849 ify=0.01. Default no object with expire time
850 -o, --overwrite=
852 The proportion of objects need overwrite, e.g.: --over‐
853 write=0.01. Default never overwrite object.
854 -R, --reconnect
856 Reconnect tests, when connection is closed it will be recon‐
857 nected.
858 -U, --udp
860 UDP tests, default memaslap uses TCP, TCP port and UDP port of
861 server must be same.
862 -a, --facebook
864 Whether it enables facebook test feature, set with TCP and
865 multi-get with UDP.
866 -B, --binary
868 Whether it enables binary protocol. Default with ASCII protocol.
869 -P, --tps=
871 Expected throughput, suffix: K, e.g.: --tps=10k.
872 -p, --rep_write=
874 The first nth servers can write data, e.g.: --rep_write=2.
875 -b, --verbose
877 Whether it outputs detailed information when verification fails.
878 -h, --help
880 Display this message and then exit.
881 -V, --version
883 Display the version of the application and then exit.
884
886 memaslap -s 127.0.0.1:11211 -S 5s
887 memaslap -s 127.0.0.1:11211 -t 2m -v 0.2 -e 0.05 -b
889 memaslap -s 127.0.0.1:11211 -F config -t 2m -w 40k -S 20s -o 0.2
891 memaslap -s 127.0.0.1:11211 -F config -t 2m -T 4 -c 128 -d 20 -P 40k
893 memaslap -s 127.0.0.1:11211 -F config -t 2m -d 50 -a -n 40
895 memaslap -s 127.0.0.1:11211,127.0.0.1:11212 -F config -t 2m
897 memaslap -s 127.0.0.1:11211,127.0.0.1:11212 -F config -t 2m -p 2
899
901 memcached(1) libmemcached(3)
9021.1 Sep 20, 2021 MEMASLAP(1)