[Haskell-cafe] Re: sendfile leaking descriptors on Linux?

[Bardur Arantsson]

On 2010-02-24 20:50, Brandon S. Allbery KF8NH wrote:
> tcpdump 'host ps3 and tcp[tcpflags] & 0x27 != 0'

(Indulging in some serious thread necromancy here, but...)

Alright, I've _finally_ got round to doing a dump with leaking file 
descriptors (or threads as the case may be).

The bits of lsof output of the leaked file descriptors looks like this 
(sorry about the wrapping):

hums       2084     bardur   36u     sock                0,6       0t0 
45022400 can't identify protocol
hums       2084     bardur   37r      REG               0,23 733054976 
  267762 THE_MOVIE.avi

So pairs of FDs are being held up by sendfile when the PS3 disconnects. 
The number of such pairs in this test run was 16.

I've attached the gzipped output from tcpdump.

The only striking thing I can see about the dump is that there are 22 
(conspicuously close to 16) sequences like:

19:45:30.135291 IP 192.168.0.115.64931 > gwendolyn.9000: Flags [R], seq 
2112225068, win 0, length 0
19:45:30.135295 IP 192.168.0.115.64931 > gwendolyn.9000: Flags [R], seq 
2112225068, win 0, length 0
19:45:30.135299 IP 192.168.0.115.64931 > gwendolyn.9000: Flags [R], seq 
2112225068, win 0, length 0
19:45:30.135302 IP 192.168.0.115.64931 > gwendolyn.9000: Flags [R], seq 
2112225068, win 0, length 0

My tcpdump-fu is rather limited, so I'm not really sure what this 
actually means... any input much appreciated.

Cheers,
-------------- next part --------------
A non-text attachment was scrubbed...
Name: dump_with_leaking_fds.log.gz
Type: application/gzip
Size: 29132 bytes
Desc: not available
Url : http://www.haskell.org/pipermail/haskell-cafe/attachments/20100325/af8b5589/dump_with_leaking_fds.log.bin