Re: [PATCH] Increase lockdep MAX_LOCK_DEPTH

Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]
From: David Chinner
Date: Friday, August 31, 2007 - 6:50 am

On Fri, Aug 31, 2007 at 08:39:49AM +0200, Peter Zijlstra wrote:

The problem is not filesystem block size, it's the xfs inode cluster buffer
size / the size of the inodes that determines the lock depth. the common case
is 8k/256 = 32 inodes in a buffer, and they all get looked during inode
cluster writeback.

This inode writeback clustering is one of the reasons XFS doesn't suffer from
atime issues as much as other filesystems - it doesn't need to do as much I/O
to write back dirty inodes to disk.

IOWs, we are not going to make the inode clusters smallers - if anything they
are going to get *larger* in future so we do less I/O during inode writeback
than we do now.....

Cheers,

Dave.
-- 
Dave Chinner
Principal Engineer
SGI Australian Software Group
-
Previous message: [thread] [date] [author]
Next message: [thread] [date] [author]

Messages in current thread:
[PATCH] Increase lockdep MAX_LOCK_DEPTH, Eric Sandeen, (Thu Aug 30, 9:43 pm)
Re: [PATCH] Increase lockdep MAX_LOCK_DEPTH, Peter Zijlstra, (Thu Aug 30, 11:39 pm)
Re: [PATCH] Increase lockdep MAX_LOCK_DEPTH, David Chinner, (Fri Aug 31, 6:50 am)
Re: [PATCH] Increase lockdep MAX_LOCK_DEPTH, Eric Sandeen, (Fri Aug 31, 7:33 am)
Re: [PATCH] Increase lockdep MAX_LOCK_DEPTH, Peter Zijlstra, (Fri Aug 31, 7:33 am)
Re: [PATCH] Increase lockdep MAX_LOCK_DEPTH, Peter Zijlstra, (Fri Aug 31, 7:36 am)
Re: [PATCH] Increase lockdep MAX_LOCK_DEPTH, David Chinner, (Fri Aug 31, 8:05 am)
Re: [PATCH] Increase lockdep MAX_LOCK_DEPTH, Peter Zijlstra, (Fri Aug 31, 8:09 am)
Re: [PATCH] Increase lockdep MAX_LOCK_DEPTH, Eric Sandeen, (Fri Aug 31, 8:11 am)
Re: [PATCH] Increase lockdep MAX_LOCK_DEPTH, David Chinner, (Fri Aug 31, 8:19 am)
Re: [PATCH] Increase lockdep MAX_LOCK_DEPTH, Josef Sipek, (Fri Aug 31, 9:33 am)