On Fri, Feb 18, 2011 at 3:48 PM, Saman Barghi <[email protected]> wrote:
> > Could you try -master? There has been fairly substantial work since the 2.8 >> release; all of the tokens in 2.8 are still taking the MP lock as a >> precaution. That is no longer the case in master. The process token has been >> broken up fairly dramatically in master as well, so I expect to see >> different results. >> > > Sorry, I am not following, by master you mean the master branch !? > Yep; we produce CD snapshots each night, they're from the latest git code as of that day. > >> Can you give us a bit more information about the h/w and configuration? In >> Kris Kennaway's tests, he was seeing FreeBSD 7 sustain 8 times the number of >> transactions you're reporting for 8.1, and that was for hardware that is >> three or four years old at this point. >> > > I see, good point. The machine I am testing on is a 4 core xeon with 2GB > of RAM, and I it is 2 to 3 years old as well (The machine Kris were using > was a "2.0Ghz 8-core amd64 system with 16GB of RAM", so as it has twice the > number of cores and 8 times more memory than what I have here, I think the > results are fair for number of transactions). I might be able to re run the > tests on another machine if I get lucky. MySQL configuration is exactly the > same as what Kris used (http://people.freebsd.org/~kris/scaling/my.cnf), I > am using MySQL 5.0.91. Here is the sysbench command : > http://people.freebsd.org/~kris/scaling/4cpu-mysql.png was on a 4 x p3 700mhz; I believe (but we should ask Kris) that the opterons were not used for the cross-OS comparisons; they were used for the fbsd 5.5 vs 6.2 vs 7.0 tests. (see the titles on that graph vs the cross-OS comparison). Happen to know what sort of Xeons exactly? > sysbench --test=oltp --num-threads=${i} --mysql-user=root --max-time=120 > --max-requests=0 --oltp-read-only=on run > > Also, I am not sure if Kris is talking about queries/sec or > transactions/sec, since he used both of them in two different graphs he > presented. What I presented is the number of transactions as reported by > sysbench, however the total number of queries are much more than this, take > a look at this: http://www.cs.uwaterloo.ca/~sbarghi/bench/queries1.jpg > Ah, okay; I only used Transactions/sec. > Also, last I tried sysbench/OLTP with MySQL on dfly, I saw MySQL making >> many 256K allocations, which fall back to mmap() in our system. mmap() >> acquires the VM token, so I expected to see a much more dramatic falloff >> than you saw. >> > > I will double check if everything is working properly and there is no > mistake in configuration of both machines. Do you remember which version of > MySQL you were using ?and What is the best way of profiling in DragonFly ?! > I used MySQL 5.1.37 I believe. Watch the output of systat -pv; you'll be able to see contended tokens. Thanks! -- vs
