Re: MySQL Performance 6.0rc1

Hi Robert,

Robert Watson wrote:
> 
> On Wed, 26 Oct 2005, Marian Hettwer wrote:
> 
>> I'm using RC1 on some of my test servers and workstations. So far, it 
>> runs very good (as in stable and fast) :) However, I thought of doing 
>> a small benchmark of MySQL in comparison to Linux 2.6.8 (Debian Sarge) 
>> and the results are kinda... shocking.
>>
>> On FreeBSD I took a pretty much generic kernel, I just removed 
>> debugging options, added SMP and changed the scheduler from BSD to 
>> ULE. I used super-smack to do a select-key test. MySQL 4.1 was build 
>> from ports with BUILD_OPTIMIZED and BUILD_STATIC
> 
> 
> Could you:
> 
> - Switch back to 4BSD
> 
yep.
by the way, back in the days of FreeBSD 4.x and 5.x, after I did a 
config MYKERNEL, it doesn't said I need to do a "make cleandepend" 
before doing a "make depend"... why that? Seems like this additional 
step in compiling the Kernel is around since 6-CURRENT, right?

Here we go with a super-smack with 4BSD (but unchanged libmap.conf)...
Kernel is apart from scheduler still the same like the on uploaded at 
http://unixoid.de/rabauke/freebsd/
I did the select-smack 4 times. This is now: 4BSD, MySQL 4.1.14, 
BUILD_STATIC, BUILD_OPTIMIZED:

select_index    200000  2       0       3776.34
select_index    200000  2       0       3802.04
select_index    200000  2       0       3809.38
select_index    200000  2       0       3796.41

Numbers are quite the same with 4BSD...


> - Use libmap to configure the mysql server to use libthr instead of
>   libpthread
>
uh. Last time I fiddled around with libmap.conf was back in FreeBSD 5.1 
... could you enlighten me a wee bit in regards to libmap.conf ? :)
If not, I'll stress google a bit and hopefully find something useful...


> And see what that does to performance using otherwise identical 
> configurations?
>
my.cnf is pretty much my-medium.cnf on Debian and FreeBSD. Although, 
Debian has MySQL 4.1.11 and FreeBSD Ports has MySQL 4.1.14.
As mentioned before, this benchmark here is a quick shot. However, the 
difference shouldn't be _that_ large (3600 vs. 14000).


> You might also consider installing MySQL 4.0.x on freebsd and linux and 
> see how they compare.  I've not looked closely, but I seem to remember 
> observing that something changed between 4.0 and 4.1 that seriously 
> impacted performance on FreeBSD, but not on Linux.  I've not had time to 
> confirm or investigate this.
>
I'll give that a shot too and see what'll happen. Hopefully I'll have a 
MySQL 4.0.x on Debian. Otherwise the pain of self compiling or debian 
packages searching starts ;)

  I'll get back with another eMail as soon as I figured the libmap.conf 
thing out and tried it with MySQL 4.0.x

best regards,
Marian