Bug 212551

Created attachment 139573 [details]
Simple C program that uses FAM

Running the test program on a FC5 machine

/home/andrew is mounted via nfs

(pts/1) [andrew@dev-b:~/programming/c]$ ./monitor /home/andrew/tmp/fam
/home/andrew/tmp/fam     FAMExists
/home/andrew/tmp/fam     FAMEndExist
a                        FAMCreated

Then doing a "touch a" in the fam directory shows the file being created.


On an FC6 machine we don't get very much.

(pts/5) [andrew@dev-d:~/programming/c]$ ./monitor /home/andrew/tmp/fam

We didn't the FAMExists or the FAMEndExist events and doing a "touch b" in the
fam directory also gives us nothing.

strace output of montior (attached program) running under FC5 and FC6 looking at
a directory in a NFS mounted filesystem.

FC5

[snip]
connect(3, {sa_family=AF_FILE, path=@/tmp/fam-andrew-}, 110) = 0
write(3, "\0", 1)                       = 1
stat("/home/andrew/tmp/fam", {st_mode=S_IFDIR|0770, st_size=6, ...}) = 0
write(3, "\36\0\1\0\1\0\2\0\24\0/home/andrew/tmp/fam", 30) = 30
select(4, [3], NULL, NULL, NULL)        = 1 (in [3])
getuid()                                = 500
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"\0", 1}], msg_controllen=0,
msg_flags=0}, 0) = 1
getsockopt(3, SOL_SOCKET, SO_PEERCRED, "\16=\0\0\364\1\0\0\364\1\0\0", [12]) = 0
read(3, "\36\0\1\0\1\0\10\0\24\0/home/andrew/tmp/fam\36\0"..., 4106) = 60
fstat(1, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 1), ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) =
0x2b47302d9000
write(1, "/home/andrew/tmp/fam     FAMExis"..., 35/home/andrew/tmp/fam     FAMExists
) = 35
select(4, [3], NULL, NULL, NULL


FC6
[snip]
connect(3, {sa_family=AF_FILE, path=@/tmp/fam-andrew-}, 110) = 0
write(3, "\0", 1)                       = 1
stat("/home/andrew/tmp/fam", {st_mode=S_IFDIR|0770, st_size=6, ...}) = 0
write(3, "\36\0\1\0\1\0\2\0\24\0/home/andrew/tmp/fam", 30) = 30
select(4, [3], NULL, NULL, NULL)        = 1 (in [3])
getuid()                                = 500
recvmsg(3, {msg_name(0)=NULL, msg_iov(1)=[{"\0", 1}], msg_controllen=0,
msg_flags=0}, 0) = 1
getsockopt(3, SOL_SOCKET, SO_PEERCRED, "Z\35\0\0\364\1\0\0\364\1\0\0", [12]) = 0
read(3,

The FC6 gnome-vfs2 uses inotify directly, not fam/gamin.
However, its meant to fall back to fam for nfs dirs.

Yes, I've noticed that things which use inotify are still working, some
ruby-inotify thing, pyinotify, inotifywatch from inotify-tools etc (as long as
the events occur on the same machine as the monitoring).

But fam does seem broke in this regards.

Well, gamin does use inotify too, so if the kernel part works this seems to be a
bug in the gamin inotify support.

Seems I have the same kind of bug but with non nfs.

When I add a music folder with nautilus into the directory from where rhythmbox
makes its database of music files, I have to make rhythmbox rescan the directory
for it to find the new subdirectory. 
On FC5, everything works smoothly without having to rescan anything and
rhythmbox apply any changes made in the directory.

Hmm, the FC5 gamin update (gamin-0.1.7-1.3.fc5) is also suffereing from this
problem. Just tested the libfam part at least, I'm now getting the FC6 output
from Comment #3 for FC5.

This is a bug in the polling backend not working (i.e. doing nothing) when using
the inotify code. I have a fix comming up.

Cool.

Cheers.

gamin-0.1.7-8.fc6 has been pushed for fc6, which should resolve this issue.  If these problems are still present in this version, then please make note of it in this bug report.

gamin-0.1.7-8.fc6 has been pushed for fc6, which should resolve this issue.  If these problems are still present in this version, then please make note of it in this bug report.