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Re: Index Add Failures

--On Tuesday, November 13, 2012 4:54 PM -0800 Howard Chu <hyc@symas.com> wrote:

Quanah Gibson-Mount wrote:
--On Tuesday, November 13, 2012 4:25 PM -0800 Howard Chu <hyc@symas.com>

I found that OSX acts different -- It actually allocates the entire
size of the database on disk, regardless of how much is used.  That
may be common to all the BSDs.

Sounds like whatever filesystem is default on BSDish systems doesn't
support sparse files.

Anyway, you can use mdb_stat to see what's in the MDB environment.

Oh, one additional note about the BSDs... I didn't see that behavior
until I enabled writemap.  Disabling writemap reverted it to the same
behavior as linux, but then of course the advantage of writemap is lost.

That's to be expected. When writemap is enabled, we ask the OS to
preallocate the entire map space. Otherwise, writing to a new page would
get a SIGBUS.

That's not quite what I see.

On Linux, you get:

[zimbra@ldap01-zcs db]$ ls -l
total 250588
-rw------- 1 zimbra zimbra 85899345920 Nov 13 17:23 data.mdb
-rw------- 1 zimbra zimbra        8192 Nov 13 17:23 lock.mdb
[zimbra@ldap01-zcs db]$ du -c -h data.mdb
245M    data.mdb
245M    total

But on OSX, the du -c -h shows 80GB as well.



Quanah Gibson-Mount
Sr. Member of Technical Staff
Zimbra, Inc
A Division of VMware, Inc.
Zimbra ::  the leader in open source messaging and collaboration