Re: mmap over nfs leads to excessive system load

From: Christoph Hellwig
Date: Wed Nov 16 2005 - 13:38:03 EST


On Wed, Nov 16, 2005 at 01:34:22PM -0500, Trond Myklebust wrote:
> Not really. The pages aren't flushed at this time. We the point is to
> gather several pages and coalesce them into one over-the-wire RPC call.
> That means we cannot really do it from inside ->writepage().
>
> We do start the actual RPC calls in ->writepages(), though.

This is a problem we have in various filesystems. Except for really
bad OOM situations the filesystem should never get a writeout request
for a single file. We should really stop having ->writepage called by
the VM and move this kind of batching code into the VM. I'm runnin into
similar issues for XFS and unwritten/delayed extent conversion once again.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/