What's your mail server running?  There was an old bug from Net/2 in
both 0.8 and 0.9 that would cause our mail.local to hang the file system
if a single person got too much mail at once.  I enclose the patch in
case you need it.

----------------------------
revision 1.7
date: 1993/08/03 00:11:29;  author: mycroft;  state: Exp;  lines: +2 -2
Don't call VOP_ADVLOCK() with the vnode locked.
----------------------------
===================================================================
RCS file: vfs_syscalls.c,v
retrieving revision 1.6
retrieving revision 1.7
diff -c2 -r1.6 -r1.7
*** 1.6 1993/08/02 23:37:56
--- 1.7 1993/08/03 00:11:29
***************
*** 32,36 ****
   *
   *    from: @(#)vfs_syscalls.c        7.74 (Berkeley) 6/21/91
!  *    $Id: vfs_syscalls.c,v 1.6 1993/08/02 23:37:56 mycroft Exp $
   */

--- 32,36 ----
   *
   *    from: @(#)vfs_syscalls.c        7.74 (Berkeley) 6/21/91
!  *    $Id: vfs_syscalls.c,v 1.7 1993/08/03 00:11:29 mycroft Exp $
   */

***************
*** 625,630 ****
        }
        vp = ndp->ni_vp;
-       fp->f_flag = fmode & FMASK;
        VOP_UNLOCK(vp);
        if (fmode & (O_EXLOCK | O_SHLOCK)) {
                lf.l_whence = SEEK_SET;
--- 625,630 ----
        }
        vp = ndp->ni_vp;
        VOP_UNLOCK(vp);
+       fp->f_flag = fmode & FMASK;
        if (fmode & (O_EXLOCK | O_SHLOCK)) {
                lf.l_whence = SEEK_SET;


(Note that this is cut and pasted, so the tabs are not tabs.)


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