1GMX-TUNE_PME(1) GROMACS GMX-TUNE_PME(1)
2
6 gmx-tune_pme - Time mdrun as a function of PME ranks to optimize set‐
7 tings
8
10 gmx tune_pme [-s [<.tpr>]] [-cpi [<.cpt>]] [-table [<.xvg>]]
11 [-tablep [<.xvg>]] [-tableb [<.xvg>]]
12 [-rerun [<.xtc/.trr/...>]] [-ei [<.edi>]] [-p [<.out>]]
13 [-err [<.log>]] [-so [<.tpr>]] [-o [<.trr/.cpt/...>]]
14 [-x [<.xtc/.tng>]] [-cpo [<.cpt>]]
15 [-c [<.gro/.g96/...>]] [-e [<.edr>]] [-g [<.log>]]
16 [-dhdl [<.xvg>]] [-field [<.xvg>]] [-tpi [<.xvg>]]
17 [-tpid [<.xvg>]] [-eo [<.xvg>]] [-px [<.xvg>]]
18 [-pf [<.xvg>]] [-ro [<.xvg>]] [-ra [<.log>]]
19 [-rs [<.log>]] [-rt [<.log>]] [-mtx [<.mtx>]]
20 [-swap [<.xvg>]] [-bo [<.trr/.cpt/...>]] [-bx [<.xtc>]]
21 [-bcpo [<.cpt>]] [-bc [<.gro/.g96/...>]] [-be [<.edr>]]
22 [-bg [<.log>]] [-beo [<.xvg>]] [-bdhdl [<.xvg>]]
23 [-bfield [<.xvg>]] [-btpi [<.xvg>]] [-btpid [<.xvg>]]
24 [-bdevout [<.xvg>]] [-brunav [<.xvg>]] [-bpx [<.xvg>]]
25 [-bpf [<.xvg>]] [-bro [<.xvg>]] [-bra [<.log>]]
26 [-brs [<.log>]] [-brt [<.log>]] [-bmtx [<.mtx>]]
27 [-bdn [<.ndx>]] [-bswap [<.xvg>]] [-xvg <enum>]
28 [-mdrun <string>] [-np <int>] [-npstring <enum>]
29 [-ntmpi <int>] [-r <int>] [-max <real>] [-min <real>]
30 [-npme <enum>] [-fix <int>] [-rmax <real>]
31 [-rmin <real>] [-[no]scalevdw] [-ntpr <int>]
32 [-steps <int>] [-resetstep <int>] [-nsteps <int>]
33 [-[no]launch] [-[no]bench] [-[no]check]
34 [-gpu_id <string>] [-[no]append] [-[no]cpnum]
35 [-deffnm <string>]
36
38 For a given number -np or -ntmpi of ranks, gmx tune_pme systematically
39 times gmx mdrun with various numbers of PME-only ranks and determines
40 which setting is fastest. It will also test whether performance can be
41 enhanced by shifting load from the reciprocal to the real space part of
42 the Ewald sum. Simply pass your .tpr file to gmx tune_pme together
43 with other options for gmx mdrun as needed.
44 gmx tune_pme needs to call gmx mdrun and so requires that you specify
46 how to call mdrun with the argument to the -mdrun parameter. Depending
47 how you have built GROMACS, values such as 'gmx mdrun', 'gmx_d mdrun',
48 or 'gmx_mpi mdrun' might be needed.
49 The program that runs MPI programs can be set in the environment vari‐
51 able MPIRUN (defaults to 'mpirun'). Note that for certain MPI frame‐
52 works, you need to provide a machine- or hostfile. This can also be
53 passed via the MPIRUN variable, e.g.
54 export MPIRUN="/usr/local/mpirun -machinefile hosts" Note that in such
56 cases it is normally necessary to compile and/or run gmx tune_pme with‐
57 out MPI support, so that it can call the MPIRUN program.
58 Before doing the actual benchmark runs, gmx tune_pme will do a quick
60 check whether gmx mdrun works as expected with the provided parallel
61 settings if the -check option is activated (the default). Please call
62 gmx tune_pme with the normal options you would pass to gmx mdrun and
63 add -np for the number of ranks to perform the tests on, or -ntmpi for
64 the number of threads. You can also add -r to repeat each test several
65 times to get better statistics.
66 gmx tune_pme can test various real space / reciprocal space workloads
68 for you. With -ntpr you control how many extra .tpr files will be writ‐
69 ten with enlarged cutoffs and smaller Fourier grids respectively. Typ‐
70 ically, the first test (number 0) will be with the settings from the
71 input .tpr file; the last test (number ntpr) will have the Coulomb cut‐
72 off specified by -rmax with a somewhat smaller PME grid at the same
73 time. In this last test, the Fourier spacing is multiplied with
74 rmax/rcoulomb. The remaining .tpr files will have equally-spaced
75 Coulomb radii (and Fourier spacings) between these extremes. Note that
76 you can set -ntpr to 1 if you just seek the optimal number of PME-only
77 ranks; in that case your input .tpr file will remain unchanged.
78 For the benchmark runs, the default of 1000 time steps should suffice
80 for most MD systems. The dynamic load balancing needs about 100 time
81 steps to adapt to local load imbalances, therefore the time step coun‐
82 ters are by default reset after 100 steps. For large systems (>1M
83 atoms), as well as for a higher accuracy of the measurements, you
84 should set -resetstep to a higher value. From the 'DD' load imbalance
85 entries in the md.log output file you can tell after how many steps the
86 load is sufficiently balanced. Example call:
87 gmx tune_pme -np 64 -s protein.tpr -launch
89 After calling gmx mdrun several times, detailed performance information
91 is available in the output file perf.out. Note that during the bench‐
92 marks, a couple of temporary files are written (options -b*), these
93 will be automatically deleted after each test.
94 If you want the simulation to be started automatically with the opti‐
96 mized parameters, use the command line option -launch.
97 Basic support for GPU-enabled mdrun exists. Give a string containing
99 the IDs of the GPUs that you wish to use in the optimization in the
100 -gpu_id command-line argument. This works exactly like mdrun -gpu_id,
101 does not imply a mapping, and merely declares the eligible set of GPU
102 devices. gmx-tune_pme will construct calls to mdrun that use this set
103 appropriately. gmx-tune_pme does not support -gputasks.
104
106 Options to specify input files:
107 -s [<.tpr>] (topol.tpr)
109 Portable xdr run input file
110 -cpi [<.cpt>] (state.cpt) (Optional)
112 Checkpoint file
113 -table [<.xvg>] (table.xvg) (Optional)
115 xvgr/xmgr file
116 -tablep [<.xvg>] (tablep.xvg) (Optional)
118 xvgr/xmgr file
119 -tableb [<.xvg>] (table.xvg) (Optional)
121 xvgr/xmgr file
122 -rerun [<.xtc/.trr/...>] (rerun.xtc) (Optional)
124 Trajectory: xtc trr cpt gro g96 pdb tng
125 -ei [<.edi>] (sam.edi) (Optional)
127 ED sampling input
128 Options to specify output files:
130 -p [<.out>] (perf.out)
132 Generic output file
133 -err [<.log>] (bencherr.log)
135 Log file
136 -so [<.tpr>] (tuned.tpr)
138 Portable xdr run input file
139 -o [<.trr/.cpt/...>] (traj.trr)
141 Full precision trajectory: trr cpt tng
142 -x [<.xtc/.tng>] (traj_comp.xtc) (Optional)
144 Compressed trajectory (tng format or portable xdr format)
145 -cpo [<.cpt>] (state.cpt) (Optional)
147 Checkpoint file
148 -c [<.gro/.g96/...>] (confout.gro)
150 Structure file: gro g96 pdb brk ent esp
151 -e [<.edr>] (ener.edr)
153 Energy file
154 -g [<.log>] (md.log)
156 Log file
157 -dhdl [<.xvg>] (dhdl.xvg) (Optional)
159 xvgr/xmgr file
160 -field [<.xvg>] (field.xvg) (Optional)
162 xvgr/xmgr file
163 -tpi [<.xvg>] (tpi.xvg) (Optional)
165 xvgr/xmgr file
166 -tpid [<.xvg>] (tpidist.xvg) (Optional)
168 xvgr/xmgr file
169 -eo [<.xvg>] (edsam.xvg) (Optional)
171 xvgr/xmgr file
172 -px [<.xvg>] (pullx.xvg) (Optional)
174 xvgr/xmgr file
175 -pf [<.xvg>] (pullf.xvg) (Optional)
177 xvgr/xmgr file
178 -ro [<.xvg>] (rotation.xvg) (Optional)
180 xvgr/xmgr file
181 -ra [<.log>] (rotangles.log) (Optional)
183 Log file
184 -rs [<.log>] (rotslabs.log) (Optional)
186 Log file
187 -rt [<.log>] (rottorque.log) (Optional)
189 Log file
190 -mtx [<.mtx>] (nm.mtx) (Optional)
192 Hessian matrix
193 -swap [<.xvg>] (swapions.xvg) (Optional)
195 xvgr/xmgr file
196 -bo [<.trr/.cpt/...>] (bench.trr)
198 Full precision trajectory: trr cpt tng
199 -bx [<.xtc>] (bench.xtc)
201 Compressed trajectory (portable xdr format): xtc
202 -bcpo [<.cpt>] (bench.cpt)
204 Checkpoint file
205 -bc [<.gro/.g96/...>] (bench.gro)
207 Structure file: gro g96 pdb brk ent esp
208 -be [<.edr>] (bench.edr)
210 Energy file
211 -bg [<.log>] (bench.log)
213 Log file
214 -beo [<.xvg>] (benchedo.xvg) (Optional)
216 xvgr/xmgr file
217 -bdhdl [<.xvg>] (benchdhdl.xvg) (Optional)
219 xvgr/xmgr file
220 -bfield [<.xvg>] (benchfld.xvg) (Optional)
222 xvgr/xmgr file
223 -btpi [<.xvg>] (benchtpi.xvg) (Optional)
225 xvgr/xmgr file
226 -btpid [<.xvg>] (benchtpid.xvg) (Optional)
228 xvgr/xmgr file
229 -bdevout [<.xvg>] (benchdev.xvg) (Optional)
231 xvgr/xmgr file
232 -brunav [<.xvg>] (benchrnav.xvg) (Optional)
234 xvgr/xmgr file
235 -bpx [<.xvg>] (benchpx.xvg) (Optional)
237 xvgr/xmgr file
238 -bpf [<.xvg>] (benchpf.xvg) (Optional)
240 xvgr/xmgr file
241 -bro [<.xvg>] (benchrot.xvg) (Optional)
243 xvgr/xmgr file
244 -bra [<.log>] (benchrota.log) (Optional)
246 Log file
247 -brs [<.log>] (benchrots.log) (Optional)
249 Log file
250 -brt [<.log>] (benchrott.log) (Optional)
252 Log file
253 -bmtx [<.mtx>] (benchn.mtx) (Optional)
255 Hessian matrix
256 -bdn [<.ndx>] (bench.ndx) (Optional)
258 Index file
259 -bswap [<.xvg>] (benchswp.xvg) (Optional)
261 xvgr/xmgr file
262 Other options:
264 -xvg <enum> (xmgrace)
266 xvg plot formatting: xmgrace, xmgr, none
267 -mdrun <string>
269 Command line to run a simulation, e.g. 'gmx mdrun' or 'gmx_mpi
270 mdrun'
271 -np <int> (1)
273 Number of ranks to run the tests on (must be > 2 for separate
274 PME ranks)
275 -npstring <enum> (np)
277 Name of the $MPIRUN option that specifies the number of ranks to
278 use ('np', or 'n'; use 'none' if there is no such option): np,
279 n, none
280 -ntmpi <int> (1)
282 Number of MPI-threads to run the tests on (turns MPI & mpirun
283 off)
284 -r <int> (2)
286 Repeat each test this often
287 -max <real> (0.5)
289 Max fraction of PME ranks to test with
290 -min <real> (0.25)
292 Min fraction of PME ranks to test with
293 -npme <enum> (auto)
295 Within -min and -max, benchmark all possible values for -npme,
296 or just a reasonable subset. Auto neglects -min and -max and
297 chooses reasonable values around a guess for npme derived from
298 the .tpr: auto, all, subset
299 -fix <int> (-2)
301 If >= -1, do not vary the number of PME-only ranks, instead use
302 this fixed value and only vary rcoulomb and the PME grid spac‐
303 ing.
304 -rmax <real> (0)
306 If >0, maximal rcoulomb for -ntpr>1 (rcoulomb upscaling results
307 in fourier grid downscaling)
308 -rmin <real> (0)
310 If >0, minimal rcoulomb for -ntpr>1
311 -[no]scalevdw (yes)
313 Scale rvdw along with rcoulomb
314 -ntpr <int> (0)
316 Number of .tpr files to benchmark. Create this many files with
317 different rcoulomb scaling factors depending on -rmin and -rmax.
318 If < 1, automatically choose the number of .tpr files to test
319 -steps <int> (1000)
321 Take timings for this many steps in the benchmark runs
322 -resetstep <int> (1500)
324 Let dlb equilibrate this many steps before timings are taken
325 (reset cycle counters after this many steps)
326 -nsteps <int> (-1)
328 If non-negative, perform this many steps in the real run (over‐
329 writes nsteps from .tpr, add .cpt steps)
330 -[no]launch (no)
332 Launch the real simulation after optimization
333 -[no]bench (yes)
335 Run the benchmarks or just create the input .tpr files?
336 -[no]check (yes)
338 Before the benchmark runs, check whether mdrun works in parallel
339 -gpu_id <string>
341 List of unique GPU device IDs that are eligible for use
342 -[no]append (yes)
344 Append to previous output files when continuing from checkpoint
345 instead of adding the simulation part number to all file names
346 (for launch only)
347 -[no]cpnum (no)
349 Keep and number checkpoint files (launch only)
350 -deffnm <string>
352 Set the default filenames (launch only)
353
355 gmx(1)
356 More information about GROMACS is available at <‐
358 http://www.gromacs.org/>.
359
361 2022, GROMACS development team
3622022.3 Sep 02, 2022 GMX-TUNE_PME(1)