Re: Possible Threading problem with -CURRENT / MySQL?

On 06/17/04 01:07, Brad Knowles wrote:
> At 1:31 AM -0400 2004-06-17, Robert Watson wrote:
>> - Removing Giant from UNIX domain sockets
> 
> Out of curiosity, is this something that could be relatively safely 
> done in general?  Any ideas on what the plan is for doing this as the
>  default on -CURRENT?

Wasn't this already done?  See this commit:
http://lists.freebsd.org/pipermail/cvs-src/2004-June/025082.html

>> - Disabling HTT - Using ADAPTIVE_MUTEXES
> 
> These both sound like typical improvements, based on what I've seen 
> on this list.  Any ideas on when they might become the default?

ADAPTIVE_MUTEXES was already enabled by default on amd64.  See this 
commit (read thread for discussion):
http://lists.freebsd.org/pipermail/cvs-src/2004-June/025234.html

It appears no comprehensive testing has been done to check whether it 
really does improve performance.  Many signs do point that way, though.

>> - Running with SCHED_4BSD instead of SCHED_ULE
> 
> This is the only one that really concerns me.  This shows that we 
> clearly need more work on ULE.  Is there one particular thing that we
>  seem to be tripping up on, or is it a multitude of things?

I think I'll switch to 4BSD until I see more work being done on ULE (I 
read cvs-src as a hobby already so I'll know when to switch back).  I 
noticed a performance drop from 5.2.1-p8 (with 4BSD) to -CURRENT (with 
ULE) when I upgraded, but I attributed it to other things.  However, the 
system still feels slower than before despite having since disabled 
INVARIANTS, WITNESS, and userspace malloc debugging flags.

Jon Noack