Re: [PATCH 00/13] Re: Scalability requirements for sysv ipc

[Nadia Derbey <Nadia.Derbey@bull.net>]

Peter Zijlstra wrote:
> On Fri, 2008-04-11 at 18:17 +0200, Nadia.Derbey@bull.net wrote:
> 
>>Here is finally the ipc ridr-based implementation I was talking about last
>>week (see http://lkml.org/lkml/2008/4/4/208).
>>I couldn't avoid much of the code duplication, but at least made things
>>incremental.
>>
>>Does somebody now a test suite that exists for the idr API, that I could
>>run on this new api?
>>
>>Mike, can you try to run it on your victim: I had such a hard time building
>>this patch, that I couldn't re-run the test on my 8-core with this new
>>version. So the last results I have are for 2.6.25-rc3-mm1.
>>
>>Also, I think a careful review should be done to avoid introducing yet other
>>problems :-(
> 
> 
> Why duplicate the whole thing, when we converted the Radix tree to be
> RCU safe we did it in-place. Is there a reason this is not done for idr?
> 
> 
> 

I did that because I wanted to go fast and try to fix the performance 
problem we have with sysV ipc's. I didn't want to introduce (yet other) 
regressions in the code that uses idr's today and that works well ;-)
May be in the future if this rcu based api appears to be ok, we can 
replace one with the other?

Regards,
Nadia