From: Paul Jackson <pj@sgi.com>
To: Herbert Poetzl <herbert@13thfloor.at>
Cc: vatsa@in.ibm.com, menage@google.com,
ckrm-tech@lists.sourceforge.net, linux-kernel@vger.kernel.org,
xemul@sw.ru, ebiederm@xmission.com, winget@google.com,
containers@lists.osdl.org, akpm@linux-foundation.org
Subject: Re: Summary of resource management discussion
Date: Fri, 16 Mar 2007 14:23:56 -0700 [thread overview]
Message-ID: <20070316142356.3b9a5597.pj@sgi.com> (raw)
In-Reply-To: <20070316141915.GA6572@MAIL.13thfloor.at>
Herbert wrote:
> looks good to me, except for the potential issue with
> the double indirection introducing too much overhear
It's not the indirection count that I worry about.
It's the scalability of the locking. We must avoid as
much as possible adding any global locks on key code paths.
This means:
1) be reluctant to add them to fork/exit
2) just RCU locks on per-job (or finer grain) data when on
the normal page allocation path
3) nothing outside the current task context for the normal
task scheduling code path.
A global lock on the wrong code path is fatal for scaling
big NUMA boxes.
... now whether or not that is an issue here, I don't claim
to know. I'm just worried that it could be.
Atomic data, such as global counters, is just as bad.
--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <pj@sgi.com> 1.925.600.0401
prev parent reply other threads:[~2007-03-16 21:23 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-03-12 12:42 Summary of resource management discussion Srivatsa Vaddagiri
2007-03-13 16:24 ` Herbert Poetzl
2007-03-13 17:58 ` Srivatsa Vaddagiri
2007-03-13 23:50 ` Herbert Poetzl
2007-03-15 11:24 ` Paul Menage
2007-03-15 17:04 ` Srivatsa Vaddagiri
2007-03-15 19:12 ` Paul Menage
2007-03-16 1:40 ` Srivatsa Vaddagiri
2007-03-16 20:03 ` Eric W. Biederman
2007-03-16 14:26 ` Herbert Poetzl
2007-03-16 14:19 ` Herbert Poetzl
2007-03-16 14:57 ` Srivatsa Vaddagiri
2007-03-16 21:23 ` Paul Jackson [this message]
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