[rt-users] Out of memory error when dumping Attachments table

[Graham Dunn]

I've asked this question on the mysql-users list, but there wasn't any
more information than what I've seen on google.

The problem is that I get an error when trying to use mysqldump to get a
backup of our Attachments table (all other tables will process fine)

/usr/local/bin/mysqldump: Error 5: Out of memory (Needed 14154840 bytes)
 when dumping table `Attachments` at row: 24285

mysql  Ver 12.22 Distrib 4.0.24, for portbld-freebsd5.3 (i386)
mysqldump  Ver 10.9 Distrib 4.1.12, for portbld-freebsd5.3 (i386)
and
mysqldump  Ver 9.11 Distrib 4.0.24, for portbld-freebsd5.3 (i386)

There are pages in the mysql online docs about setting variables in
/boot/loader.conf to avoid the 512MB per-process limit in FreeBSD:

seisei# more /boot/loader.conf
set console=comconsole
kern.maxdsiz="1G"
# kern.dfldsiz="751619277" # 750 MB
kern.maxssiz="134217728" # 128MB

No change after reboot.

FreeBSD seisei.cs.myharris.net 5.3-RELEASE-p9 FreeBSD 5.3-RELEASE-p9 #0:
Wed Apr 20 13:14:54 EDT 2005
root at atarashii.inscriber.local:/usr/obj/usr/src/sys/GENERIC  i386

vm.vmtotal:
System wide totals computed every five seconds: (values in kilobytes)
===============================================
Processes:              (RUNQ: 1 Disk Wait: 0 Page Wait: 0 Sleep: 58)
Virtual Memory:         (Total: 1823K, Active 1132540K)
Real Memory:            (Total: 1009492K Active 708436K)
Shared Virtual Memory:  (Total: 40948K Active: 26944K)
Shared Real Memory:     (Total: 37572K Active: 24768K)
Free Memory Pages:      48428K

I'm really grasping at straws here. Is there a way to back up the table
incrementally so that the smaller chunks don't hit the memory limit?

Thanks,
Graham