Re: Index Add Failures

[Quanah Gibson-Mount <quanah@zimbra.com>]

--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>
> > wrote:
> >
> > > > 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.
> > :P
>
> 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


--

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