[Imap-uw] imapd busy loop

Mark Crispin MRC at CAC.Washington.EDU
Fri Nov 2 15:13:22 PDT 2007


I think that something else may be happening. Is the user over quota?

The session must have autologged out, gotten a hangup signal, or
encountered a fatal I/O error; otherwise it would not have state == LOGOUT
with a stream still open.

The loop should only take place if LOCAL->dirty is set, but unix_rewrite()
clears LOCAL->dirty if it succeeded.

Try the following patch and see if it remedies the loop. It doesn't
really address the problem that the mailbox couldn't be updated though.

*** imapd.c~ 2007-10-12 11:12:37.000000000 -0700
--- imapd.c 2007-11-02 15:08:46.000000000 -0700
***************
*** 378,383 ****
--- 378,385 ----
}

if (setjmp (jmpenv)) { /* die if a signal handler say so */
+ /* in case we get borked now */
+ if (setjmp (jmpenv)) _exit (1);
/* need to close stream gracefully? */
if (stream && !stream->lock && (stream->dtb->flags & DR_XPOINT))
stream = mail_close (stream);

On Fri, 2 Nov 2007, Kostik wrote:


> Hello.

>

> I am trace looping proc in GDB. And see, that it loop's in unix_check at

> unix.c:822.

>

> ====================

> 0x0809dace in unix_check (stream=0x8142738) at unix.c:826

> 826 in unix.c

> (gdb) where

> #0 0x0809dace in unix_check (stream=0x8142738) at unix.c:826

> #1 0x0809db29 in unix_close (stream=0x8142738, options=0) at unix.c:577

> #2 0x080693fa in mail_close_full (stream=0x8142738, options=0) at mail.c:1354

> #3 0x08051438 in main (argc=1, argv=0xbffffae4) at imapd.c:383

> ====================

>

> Step-by-step debuging:

>

> in 'unix_check'(unix.c:826) do:

> step1: in 822 str: "unix_rewrite" return 0 and go to 'else'

> step2: else unix_unlock (LOCAL->fd,stream,&lock);

> step3: mail_unlock (stream); /* unlock the stream */

> step4: MM_NOCRITICAL (stream)

> ==> go to "mm_nocritical (s=0x8142738) at imapd.c:4419"

>

> in 'mm_nocritical':

> step5: if (!--critical && (state == LOGOUT)) {; _is TRUE_

> step6: if (s && (stream != s) && !s->lock && (s->dtb->flags &

> DR_XPOINT)); _is FALSE_

> step7: longjmp (jmpenv,1); /* die now */

> ==> go to "main (argc=1, argv=0xbffffae4) at imapd.c:382"

>

> in 'main':

> step8: if (stream && !stream->lock && (stream->dtb->flags &

> DR_XPOINT)); _is TRUE_

> step9: stream = mail_close (stream);

> ==> go to "mail_close_full (stream=0x8142738, options=0) at mail.c:135"

>

> in 'mail_close_full':

> step10: if (stream) {; _is TRUE_

> step11: if (stream->dtb) (*stream->dtb->close) (stream,options);

> ==> go to: "unix_close (stream=0x0, options=0) at unix.c:571"

>

> in 'unix_close':

> step12: int silent = stream->silent;

> step13: stream->silent = T; /* go silent */

> again

> step14: int silent = stream->silent;

> step15: stream->silent = T; /* go silent */

> again

> step16: int silent = stream->silent;

> and

> step17: if (options & CL_EXPUNGE) unix_expunge (stream,NIL,NIL); _is

> FALSE_

> step18: else if (LOCAL->dirty) unix_check (stream);

>

> AND WE AGIAN GO to:

> unix_check (stream=0x8142738) at unix.c:816

>

> It's looping. Does anybody can help?

>

> =koc

>

> K> Hello everyone!

>

> K> We have imap-2006k.DEV.SNAP-0710261815 at Linux (Slackware_11 Linux

> K> 2.4.35.3). And NFS(v3) mounted mailbox store with Disk quota enabled.

>

> K> Imapd busy loop is:

> K> ===| strace begin |==============================

>

>>> uname({sys="Linux", node="gnome11", ...}) = 0

>>> open("/var/virtual/online.ru/mail/W/Z/mivanov.lock.1193931164.28319.gnome11", O_WRONLY|O_CREAT|O_EXCL, 0666) = 0

>>> close(0) = 0

>>> link("/var/virtual/online.ru/mail/W/Z/mivanov.lock.1193931164.28319.gnome11", "/var/virtual/online.ru/mail/W/Z/mivanov.lock") = 0

>>> stat64("/var/virtual/online.ru/mail/W/Z/mivanov.lock.1193931164.28319.gnome11", {st_mode=S_IFREG|0666, st_size=0, ...}) = 0

>>> unlink("/var/virtual/online.ru/mail/W/Z/mivanov.lock.1193931164.28319.gnome11") = 0

>>> umask(022) = 0

>>> chmod("/var/virtual/online.ru/mail/W/Z/mivanov.lock", 0666) = 0

>>> open("/var/virtual/online.ru/mail/W/Z/mivanov", O_RDWR) = 0

>>> fstatfs(0, {f_type="NFS_SUPER_MAGIC", f_bsize=32768, f_blocks=6690853, f_bfree=4189342, f_bavail=3854123, f_files=3352576, f_ffree=1626667, f_fsid={0,

>>> 0}, f_namelen=255, f_frsize=0}) = 0

>>> fstat64(0, {st_mode=S_IFREG|0600, st_size=6840320, ...}) = 0

>>> time(NULL) = 1193931164

>>> time(NULL) = 1193931164

>>> lseek(0, 6840320, SEEK_SET) = 6840320

>>> write(0, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 65) = 65

>>> | 00000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ........ ........ |

>>> | 00010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ........ ........ |

>>> | 00020 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ........ ........ |

>>> | 00030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ........ ........ |

>>> | 00040 00 . |

>>> fsync(0) = -1 EDQUOT (Disk quota exceeded)

>>> ftruncate(0, 6840320) = 0

>>> fsync(0) = 0

>>> time(NULL) = 1193931164

>>> fstat64(0, {st_mode=S_IFREG|0600, st_size=6840320, ...}) = 0

>>> utime("/var/virtual/online.ru/mail/W/Z/mivanov", [2007/11/01-18:32:44, 2007/11/01-18:32:43]) = 0

>>> fstatfs(0, {f_type="NFS_SUPER_MAGIC", f_bsize=32768, f_blocks=6690853, f_bfree=4189342, f_bavail=3854123, f_files=3352576, f_ffree=1626666, f_fsid={0,

>>> 0}, f_namelen=255, f_frsize=0}) = 0

>>> unlink("/var/virtual/online.ru/mail/W/Z/mivanov.lock") = 0

>>> close(0) = 0

>>> lstat64("/var/virtual/online.ru/mail/W/Z/mivanov.lock", 0xbfffd0ac) = -1 ENOENT (No such file or directory)

>>> umask(0) = 022

>>> getpid() = 28319

>>> time(NULL) = 1193931164

>

> K> And again....

>>> uname({sys="Linux", node="gnome11", ...}) = 0

> K> ................

>

> K> ===| strace end |==============================

>

> K> Any other suggestions or troubleshooting ideas?

> K> Thanks for your help!

>

>

>

> _______________________________________________

> Imap-uw mailing list

> Imap-uw at u.washington.edu

> https://mailman1.u.washington.edu/mailman/listinfo/imap-uw

>


-- Mark --

http://staff.washington.edu/mrc
Science does not emerge from voting, party politics, or public debate.
Si vis pacem, para bellum.


More information about the Imap-uw mailing list