misc/66270: dump causes machine freeze

[dane foster]

The following reply was made to PR misc/66270; it has been noted by GNATS.

From: dane foster <dene at slush.ca>
To: Kris Kennaway <kris at obsecurity.org>
Cc: freebsd-gnats-submit at FreeBSD.org
Subject: Re: misc/66270: dump causes machine freeze
Date: Wed, 5 May 2004 17:53:30 +1200

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 One more thing before I forget, I've made two small modifications to 
 dump's main.c
 One mod to default to always snapshot, and one mod to hardcode the path 
 to mksnap_ffs, I'll attach the diff
 
 I appreciate you looking into this, and once again, any more info I can 
 provide, just let me know.
 
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 --- main.c      Sun Apr 25 13:30:06 2004
 +++ main.c.orig Sun Nov 16 20:01:58 2003
 @@ -75,7 +75,7 @@
  #include "pathnames.h"
  
  int    notify = 0;     /* notify operator flag */
 -int    snapdump = 1;   /* dumping live filesystem, so use snapshot */
 +int    snapdump = 0;   /* dumping live filesystem, so use snapshot */
  int    blockswritten = 0;      /* number of blocks written on current tape */
  int    tapeno = 0;     /* current tape number */
  int    density = 0;    /* density in bytes/0.1" " <- this is for hilit19 */
 @@ -322,7 +322,7 @@
                         snprintf(snapname, sizeof snapname,
                             "%s/.snap/dump_snapshot", mntpt);
                         snprintf(snapcmd, sizeof snapcmd,
 -                           "/sbin/mksnap_ffs %s %s", mntpt, snapname);
 +                           "mksnap_ffs %s %s", mntpt, snapname);
                         unlink(snapname);
                         if (system(snapcmd) != 0)
                                 errx(X_STARTUP, "Cannot create %s: %s\n",
 
 
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 On May 5, 2004, at 5:04 PM, Kris Kennaway wrote:
 
 > Dane Foster wrote:
 >
 >>> Number:         66270
 >>> Category:       misc
 >>> Synopsis:       dump causes machine freeze
 >>> Confidential:   no
 >>> Severity:       serious
 >>> Priority:       medium
 >>> Responsible:    freebsd-bugs
 >>> State:          open
 >>> Quarter:        Keywords:       Date-Required:
 >>> Class:          sw-bug
 >>> Submitter-Id:   current-users
 >>> Arrival-Date:   Tue May 04 18:30:20 PDT 2004
 >>> Closed-Date:
 >>> Last-Modified:
 >>> Originator:     Dane Foster
 >>> Release:        5.2.1
 >>> Organization:
 >>> Environment:
 >> FreeBSD homer.connect.com.fj 5.2.1-RELEASE FreeBSD 5.2.1-RELEASE #0: 
 >> Tue May  4 22:38:11 FJT 2004     
 >> root at homer.connect.com.fj:/usr/src/sys/i386/compile/IBM  i386
 >>> Description:
 >
 >>      dump (called via amanda) with snapshots on a large, volatile 
 >> filesystem causes the machine to freeze. no errors reported
 >
 > This PR contains even less information that your non-PR email, but 
 > what you're describing sounds like intended behaviour.  Specifically, 
 > creating a snapshot causes all other filesystem access to pause until 
 > the creation is complete, which can take a long time on large or 
 > active filesystems.
 >
 > Can you please confirm that if you wait long enough the operation 
 > completes?
 >
 > Kris
 >
 
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