Privet Sergey,
do not think I have a problem with my config(s). I am not on the machine at the moment. From memory, with 16 Cores / 32 VCPU, 64 GB memory, buffer pools, logs etc. tailored to this configuration, the TPS rate is 64 threads - R/O 73K R/W 26K 128 threads - R/O 71K R/W 23K. I am putting the DB in RAM of course to obviate I/O issues. I am interested in seeing what is happening with the CPU caches and nest.. NMON tells me that for the R/O runs I have approximately 85% User, 12-14% System and the rest Idle - this stays consistent throughout the run (300 seconds R/O, 600 seconds R/W) which is reasonable. On the R/W runs, NMONs CPU usage display shows that some CPUs are barely firing, or only intermittently and the granularity I had with R/O is gone. This would seem to tie in with what I see in the MariaDB log - headwinds, violent storms and deadlocks. Any further information you require, please let me know. Regards, JC Hi! I just tried this on x86: 40 threads against single table having 10k rows. No deadlocks, "tps: 12372.40, reads: 173219.52, writes: 49490.51". This is with latest snapshot of 10.1 and sysbench 1.0. I believe you shouldn't see deadlocks on such a big data set. Probably something is wrong with your configs? Regards, Sergey On Thu, Jun 08, 2017 at 04:51:31PM +0200, J. Cassidy wrote: > > > Hello Mark, > > appreciate the reply. > > The OLTP table size and > OLTP size give me a DB size of appx 12GB. This is what I want. I have in the > meantime, looked at some older logs and see that whatever amount of threads I > specify (8, 16,32, 64 or 128), the deadlock messages are still surfacing in the > R/W phase > of Sysbench. I even dropped in two different MariaDB release levels > (10.0.19, 10.1.24) to see whether it would make a difference, deadlock still > there. I am using Sysbench 0.5 for these tests. > I am currently using MariaDB > 10.1.24 - built directly on the machine. S390x by the way, but the problem is > also > occuring on an X86-64 box. > > Regards, > > > JC > > > > I run sysbench frequently with MySQL > (not MariaDB yet) and don't recall ever seeing this error. But I use much > larger values for --oltp-table-size. You used 85937 and I use 1M or larger. > Maybe > there is too much data contention with smaller tables, even if a large number of > tables is used (128 in your case). I use a smaller number of tables - between 4 > and 20. On Thu, Jun 8, 2017 at 12:48 AM, J. Cassidy s...@jdcassidy.eu> wrote: > Hello all, > > > have used Sysbench extensively to test MariaDB CPU load factors between various > architectures. > > I am noticing massive amounts of "[ERROR] mysqld: > Deadlock found when trying to get lock; try restarting transaction" in the > MariaDB error log during the R/W phase. The Sysbench R/W TPS rates are still > respectable for my purposes, but how do I > correct this condition?? Can I > ignore this / must live with it? > I have tried three different MariaDB > releases (10.0.19, 10.1.12, 10.1.24) to narrow things down, but this message (x > 1000's) is happening across all releases in the Sysbench R/W phase. > > Here is the Sysbench command that drives the workload against MariaDB - > > sysbench --test=lua/oltp.lua --oltp_tables_count=128 --oltp-table-size=85937 > --rand-seed=42 --rand-type=uniform --num-threads=128 --oltp-read-only=off > --report-interval=2 --mysql-socket=/var/lib/mysql/mysql.sock --max-time=201 > --max-requests=0 --mysql-user=root --percentile=99 run > > Would anyone > have a tip / idea /pointer? > > > Regards, > > > JC > > > John Cassidy > > Obere Bühlstrasse 21 > 8700 Küsnacht > (ZH) > Switzerland / Suisse / Schweiz > > > Mobile: +49 152 58961601 (Germany) > Mobile: +352 621 577 149 (Luxembourg) > Mobile: +41 78 769 17 97 (CH) > Landline: +41 44 509 1957 > > http://www.jdcassidy.eu > > "Aut viam inveniam aut > faciam" - Hannibal. > _______________________________________________ > Mailing list: https://launchpad.net/~maria-discuss > Post to : > maria-discuss@lists.launchpad.net > Unsubscribe : https://launchpad.net/~maria-discuss > More help : https://help.launchpad.net/ListHelp > --Mark Callaghan > mdcal...@gmail.com > > John Cassidy > > Obere Bühlstrasse 21 > 8700 > Küsnacht (ZH) > Switzerland / Suisse / Schweiz > > > Mobile: > +49 152 58961601 (Germany) > Mobile: +352 621 577 149 (Luxembourg) > Mobile: > +41 78 769 17 97 (CH) > Landline: +41 44 509 1957 > > http://www.jdcassidy.eu > > "Aut viam inveniam aut faciam" - > Hannibal. > _______________________________________________ > Mailing list: https://launchpad.net/~maria-discuss > Post to : maria-discuss@lists.launchpad.net > Unsubscribe : https://launchpad.net/~maria-discuss > More help : https://help.launchpad.net/ListHelp John Cassidy Obere Bühlstrasse 21 8700 Küsnacht (ZH) Switzerland / Suisse / Schweiz Mobile: +49 152 58961601 (Germany) Mobile: +352 621 577 149 (Luxembourg) Mobile: +41 78 769 17 97 (CH) Landline: +41 44 509 1957 http://www.jdcassidy.eu "Aut viam inveniam aut faciam" - Hannibal.
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