Hi!
Could someone run a primitive benchmark? Like ‘7z b’ or so?
Hi!
Could someone run a primitive benchmark? Like ‘7z b’ or so?
Sure. I’d just done a fresh Fedora re-installation. A serial console was used. No network connection was available and the system was at runlevel S.
I didn’t (and won’t) download and bench from source comparing gcc vs. llvm and custom kernals, compare compiler flags, and all that. Gotta leave that for Phoronix.
Since I was working in another window and didn’t (still don’t) know much about 7z, I assumed it was single threaded and decided to fire off a second copy to saturate both cores. HUGE misunderstanding.
7z b > /tmp/1
7z b &
7z b &
wait
) > /tmp/2
I understand now that a single 7z will use as many cores as it can find and as much RAM as it thinks is available - eek! - so the second was surely context swiitching itself silly with 4 cores instead of 2 and very likely running large numbers of data (and maybe text) fetches and stores to backing swap or un-dirtyable store. As a sysop, one would work hard to avoid either case, so running out of both CPU and RAM at the same time is more of an OS stress test than it is a benchmark of the app itself.
A single copy clocks in at 3 wall-minutes:
real 2m56.025s
user 5m12.792s
sys 0m6.797s
Comparing the timestamps on /tmp/1 and /tmp/2, we see that running it twice at the same time takes 8 minutes. This seems expected as they’re essentially running serially and with the penalty of paging/swapping. Don’t do that.
/tmp/1:
7-Zip 16.02 : Copyright (c) 1999-2016 Igor Pavlov : 2016-05-21
p7zip Version 16.02 (locale=en_US.UTF-8,Utf16=on,HugeFiles=on,64 bits,2 CPUs LE)
LE
CPU Freq: 32000000 64000000 64000000 64000000 - 256000000 512000000 1024000000 2048000000
RAM size: 7174 MB, # CPU hardware threads: 2
RAM usage: 441 MB, # Benchmark threads: 2
Compressing | Decompressing
Dict Speed Usage R/U Rating | Speed Usage R/U Rating
KiB/s % MIPS MIPS | KiB/s % MIPS MIPS
22: 781 165 462 760 | 19372 200 828 1654
23: 765 169 462 780 | 19133 199 832 1656
24: 744 169 473 801 | 18639 198 825 1636
25: 744 174 487 850 | 18276 199 817 1627
---------------------------------- | ------------------------------
Avr: 169 471 798 | 199 825 1643
Tot: 184 648 1221
cat /tmp/2
7-Zip 16.02 : Copyright (c) 1999-2016 Igor Pavlov : 2016-05-21
p7zip Version 16.02 (locale=en_US.UTF-8,Utf16=on,HugeFiles=on,64 bits,2 CPUs LE)
LE
CPU Freq: 64000000 - - 64000090 128000000 256000000 - - 2048000000
RAM size: 7174 MB, # CPU hardware threads: 2
RAM usage: 441 MB, # Benchmark threads: 2
Compressing | Decompressing
Dict Speed Usage R/U Rating | Speed Usage R/U Rating
KiB/s % MIPS MIPS | KiB/s % MIPS MIPS
22: 453 100 442 441 | 9792 101 824 836
23: 405 95 436 413 | 9492 101 818 822
24: 417 101 444 449 | 9271 100 811 814
25: 398 100 457 455 | 9143 101 804 814
---------------------------------- | ------------------------------
Avr: 99 445 439 | 101 814 821
Tot: 100 629 630
7-Zip 16.02 : Copyright (c) 1999-2016 Igor Pavlov : 2016-05-21
p7zip Version 16.02 (locale=en_US.UTF-8,Utf16=on,HugeFiles=on,64 bits,2 CPUs LE)
LE
CPU Freq: 64000000 64000000 64000000 - - - 512000000 1024000000 2048000000
RAM size: 7174 MB, # CPU hardware threads: 2
RAM usage: 441 MB, # Benchmark threads: 2
Compressing | Decompressing
Dict Speed Usage R/U Rating | Speed Usage R/U Rating
KiB/s % MIPS MIPS | KiB/s % MIPS MIPS
22: 413 92 438 403 | 9789 101 828 836
23: 421 99 434 429 | 9552 100 824 827
24: 409 99 444 440 | 9402 102 811 825
25: 389 98 455 445 | 9799 108 806 872
---------------------------------- | ------------------------------
Avr: 97 443 429 | 103 817 840
Tot: 100 630 635
Two parallel copies doesn’t destroy the system, but it does result in poorer behaviour than letting the app decide on its own how deep and wide it should run.
Oh, thank you so much.