Corinna Vinschen wrote:
On Apr 30 01:58, Charles Wilson wrote:Well, one of the differences between ftpd-1.3.2 and ftpd-1.5 is that the newer version uses mmap on the (local) file. ftpd.c is the /only/ source file in inetutils that uses mmap.Ok, so the ftpd using mmap is faster, one way or another.
Not according to my numbers: mmap, topo 1, 4k buffers: 9-10 Mbps mmap, topo 2, 4k buffers: 14-15 Mbps NO mmap, topo 1, 4k bufs: 9-10 Mbps NO mmap, topo 2, 4k bufs: 14-15 Mbps
If [disabling mmap] *does* fix the problem, it may point to an issue with cygwin-1.5's mmap implementation, or with XP's handling of the underlying NtCreateSection()...mmap is not supposed to be CPU-intensive.There might be a bug lurking somewhere. Could you create a very simple testcase which basically behaves like ftpd for debugging?
attached.
gcc -o server server.c
gcc -o client client.c
Add an entry to /etc/services on both machines, like:
example 22725/tcp
or you could edit the two files and use a hardcoded port number, instead
of a service name and getservbyname()
And don't forget to open a hole in your server machine's firewall for that port.
On the server machine, invoke as: $ server <filename>This file is the one that will be transferred to the client. This works for me:
$ dd if=/dev/urandom of=ReallyBigFile bs=1M count=250 On the client: $ client <hostname_of_server> <filename> <filename> is where the client will save the transferred data.server is a traditional daemon, which forks off a copy to handle each new connection. That copy is the one you want to debug/strace/whatever.
With this pair of programs, I saw "sane" memory usage in all cases when NOT using mmap, and I saw "insane" memory usage for all mmap cases except when blocksize was 1k.
To switch among the various cases, edit the server.c file to #define/#undef HAVE_MMAP, and change the value of LARGE_TRANSFER_BLOCKSIZE.
-- Chuck
ftpd-mmap-troubles.tar.bz2
Description: Binary data
-- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
