> often I get "CIFS VFS: server not responding". > together with "CIFS VFS: No response for cmd 50 mid xxx" The xxx number > seems to vary. The problem seems to be triggered by any operation > which touches lots of files quickly. E.g. > by copying source file directories onto or from it or simply by find. > > Copying single larger files (I generated a 100MB file with dd) don't seems > to hurt. > > Interestinly -- this is where the really strange part comes -- it seems to > work on the client which has debian Etch
There are a couple of common ways to attack this kind of problem, to identify if the server is hanging up or the client or network stack is losing the response. There were some (now fixed) bugs in cifs_demultiplex_thread (whose frequency should have been very rare, but seemed to be more common on some distros) which could cause responses to be discarded by the client. I typically would run a wireshark trace so I could look at whether the server really did respond (you can look at the mid to correlate the trace with the dmesg log warning). There is another way to see if the server is getting slow (but not so slow that the client is giving up) - by turning on CONFIG_CIFS_STATS2 (CIFS "Extended Statistics" in menuconfig) in which case "slow" (longer than 1 second) responses are logged. This can show problems with the server response long before we reach the catastrophic more than 20 second delays you may be seeing. You may want to build the current cifs backport of the most recent fixes for cifs.ko (source at http://pserver.samba.org/samba/ftp/cifs-cvs/cifs-1.50c.tar.gz) to see if the problem is problem was on the client and is already fixed. There is one additional EAGAIN handling problem in cifs_demultiplex which is in mainline but not in the cifs backport yet which will be in cifs 1.51 (which should be out later in the month). -- Thanks, Steve - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/