Messages in this thread Patch in this message | | | Subject | Re: pdflush eating a lot of CPU on heavy NFS I/O | From | Trond Myklebust <> | Date | Thu, 29 Apr 2004 00:21:55 -0400 |
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On Wed, 2004-04-28 at 23:55, Brent Cook wrote:
> ozma:/home /home nfs rw,v3,rsize=8192,wsize=8192,hard,udp,lock,addr=ozma 0 0
OK, then it's not the case that it is doing synchronous I/O.
I see that we're failing to set wbc->encountered_congestion in the case where a nonblocking writeback is forced to exit due to congestion. Could that be causing pdflush to loop Andrew?
If so, does the following patch help?
--- linux-2.6.6-rc3/fs/nfs/write.c.orig 2004-04-28 22:25:46.000000000 -0400 +++ linux-2.6.6-rc3/fs/nfs/write.c 2004-04-29 00:06:25.000000000 -0400 @@ -347,8 +347,10 @@ int nfs_writepages(struct address_space if (err) return err; while (test_and_set_bit(BDI_write_congested, &bdi->state) != 0) { - if (wbc->nonblocking) + if (wbc->nonblocking) { + wbc->encountered_congestion = 1; return 0; + } nfs_wait_on_write_congestion(mapping, 0); } err = nfs_flush_inode(inode, 0, 0, wb_priority(wbc)); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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