On Tue, 27 Sep 2011 16:36:22 -0500 Steve French <smfrench@xxxxxxxxx> wrote: > FYI - The cifs async write in 3.0 seems to exacerbate problems running > out of memory (apparently) on the Windows 7 system (running as a > server) after a large file copy to the server completes. I have been > able to reproduce the same problem on Windows Vista Service Pack 2 > (which is a good news/bad news story since my earlier testing on > Windows Vista showed hangs on some requests rather than returning out > of memory). Does not seem to be a problem with any of the Windows > server versions just Windows 7 and Vista so far. > > As Pavel noted in an earlier note, increasing MaxWorkItems to 4096 in > the Windows registry solves this. > > The cifs async write code does increase large file copy speed > dramatically (more than 15% in most environments) - but we are working > through how to handle the Windows7/WindowsVista problem to see if > there are workarounds. > This is seems likely to be a cifs.ko bug -- it does not respect the MaxReq parm that the server sends in the negotiate and instead uses a hardcoded limit of 50 requests (which is tunable via module parm). What value is the server sending in the NEGOTIATE? Ensuring that cifs.ko doesn't exceed that value seems like a worthwhile endeavor. This is likely to be even worse soon when the async read patches are merged. -- Jeff Layton <jlayton@xxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-cifs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
