I noted an extremely poor performance when copying big files from a windows xp client to a samba share. The exact version of samba does not seem to matter: I tried several different samba servers with versions between 3.014 and 3.0.23b running on Linux 2.4.32 and 2.6.17 (machines and network otherwise idle, clients connected via fast ethernet, servers via Gbit; network performance in both directions around 95 Mbit/s). I made several tests copying a 1GB file with Windows 98 and Windows XP clients. Reading the file from the server takes predictably around 105 seconds (~9.75 MB/s).
Writing to the server takes only slightly longer on Win98 (130 seconds, ~8 MB/s) while the same takes approximately 45 minutes from a XP client (I don't know whether this matters, I noted that on the XP write test, the directory listing on the server immediately shows a file with the final size - obviously a sparse file, repeatedly invoking du shows the gradually increasing actual size). I wrote a little test program that just writes data to a file and shows the throughput; the transfer rates I get that way are pretty reasonable, so it is not a general problem but something that only occurs on specific operations like copying. Tracing the network traffic also didn't tell me what the problem might be: XP uses for copying as well as for other write operations WriteAndXRequest, the only peculiarity I noticed is the slightly exotic block size of 61440 bytes per request when copying (which also doesn't seem to be the problem - Win98 uses the same block size with WriteRaw) Has anybody else made similar experiences? (Since I could see this issue with differently configured servers/clients, it should not be just my personal problem. Of course in most settings where the data usually goes mostly from the server to the client it is not obvious) Any ideas what's going on and what to do about it? -- To unsubscribe from this list go to the following URL and read the instructions: https://lists.samba.org/mailman/listinfo/samba
