Consequences of a large mailbox

[dancecom...@hotmail.com]

Hi everyone,

Does the size of a mailbox affect the performance of outlook for the
large mailbox user, or the performance of exchange for all users, or
both, or neither? Or does the number of items in the mailbox affect the
performance?

We have around 50 mailboxes on Exchange 6. 6 of the are over 1Gb in
size (avg. 18,000 items), the largest being 4.4Gb (22,500 items). Most
of the others are on average around 200Mb (avg. 2,000 items). Outlook
run slow on some users with larger mailboxes and many users with
smaller mailboxes comlain that it's getting slower. They complain that
outlook is too slow, and they don't have time to wait around, and they
obviously don't have time to 'mess around' removing attachments or
deleting/organising mail.

Would reducing the mailbox sizes increase performance, ie. stop
'requesting data from server' messages from appearing so often and
increase speed of loading outlook and sending/receiving messages?

Our PC's are a decent spec, the server is 2.0ghz with 2gb ram and a
124gb drive with 13gb free. So I'm guessing it should run fine on the
hardware we have.

Hope someone can help.

Cheers,

Richard Thorneycroft

[Siegfried]

If your organisation has as big mailboxes i think it is better to work with
pst. The performance is decreasing rapidly if you have few mailboxes with
more than 2 to more GB . Maybe you can try to archive the big mailboxes.

But the better way is to setup a mailbox limit!
The users will get excited about that but they learn to live with this rules
;)

regards
Siegfried

[dancecom...@hotmail.com]

Thanks for your help, I'll take the relevent measures to get this
sorted.

Cheers,

Richard

[Ben Winzenz [Exchange MVP]]

Running your server with a single hard drive is likely the culprit - you
just aren't going to be able to get the I/O performance you are needing from
a single drive. Switching to PST's may make a difference to some users, but
it isn't a move I would recommend. The net result would be that users with
large mailboxes would probably see the same slowness, users with small
mailboxes would be fine, but none of the mail would be stored on the
Exchange server, making disaster recovery a BIG issue.

That being said, mailbox size definitely affects the performance of Outlook,
but what perhaps affects performance even more is the number of items in the
default system folders (Inbox, Sent Items, etc.). If there are more than a
few thousand items in any of those folders, performance will likely suffer.
A much better practice would be to create additional folders and sort mail
from the inbox into one of those folders.

If you are seeing "Outlook requesting data" messages, I'd take a look at the
following article, which should help you determine where your bottleneck is
(though I'd wager it is disk).

Exchange 2000:
http://www.microsoft.com/technet/prodtechnol/exchange/2000/support/trouperf.mspx
Exchange 2003:
http://www.microsoft.com/downloads/details.aspx?familyid=8679f6bd-7ff0-41f5-bdd0-c09019409fc0&displaylang=en

--
Ben Winzenz
Exchange MVP
MessageOne

<dancecom...@hotmail.com> wrote in message
news:1121079960.7...@f14g2000cwb.googlegroups.com...

[dancecom...@hotmail.com]

Thanks for that, we have two disks, that is the one with exchange on it
though. The other is 12gb. I'll take a look at the article see if it
helps. Cheers.

[Ed Crowley [MVP]]

Not really. The one place I know of where performance can take a hit is
when a user has thousands of mail items in a folder, in which case there can
be an annoying delay while Exchange renders the folder view. But large
mailboxes in themselves don't cause performance problems that I've seen.
--
Ed Crowley
Celebrating a decade of Exchange peer support

<dancecom...@hotmail.com> wrote in message
news:1121079960.7...@f14g2000cwb.googlegroups.com...

[Hank Arnold]

Assuming he meant Exchange 5.5, IIRC, the maximum PST file is 2GB...

--
Regards,
Hank Arnold

"Siegfried" <Sieg...@discussions.microsoft.com> wrote in message
news:343FEE42-101E-401C...@microsoft.com...

[Hank Arnold]

Ben,

Is there a corresponding article for 5.5? We are experiencing frequent
"requesting data" and we won't be migrating to Exchange 2003 until some time
next year (non-profit $$'s).

--
Regards,
Hank Arnold

"Ben Winzenz [Exchange MVP]" <ben_winzenz@NOSPAMdotmessageonedotcom> wrote
in message news:OnxLMyih...@TK2MSFTNGP09.phx.gbl...

[spivvy]

we have used PST files with exch 5.5 and noticed that the bigger pst files do
show a degrade in performance ,the delay is mainly on opening the pst folder
,also it seems to affect people more if they have multiple sub folders on
their pst files .

[Andy David - MVP]

On Tue, 12 Jul 2005 03:49:02 -0700, spivvy
<spi...@discussions.microsoft.com> wrote:

>we have used PST files with exch 5.5 and noticed that the bigger pst files do
>show a degrade in performance ,the delay is mainly on opening the pst folder
>,also it seems to affect people more if they have multiple sub folders on
>their pst files .

Sure, PSTs , but those are not the same as mailboxes :)

[Ben Winzenz [Exchange MVP]]

I'm not sure - I don't have it bookmarked like the other two. Many of the
same perfmon counters should apply regardless of Exchange version, though
they may be slightly different. The main point of the article is to help
you determine where the bottleneck is and what is causing the requesting
data problem. There are typically 3 causes. Server (which can then be
sub-divided into memory, disk, cpu, etc.), network, and client. By
monitoring the perfmon counters, it should help you figure out where the
problem lies, and then dig deeper at that level.

--
Ben Winzenz
Exchange MVP
MessageOne

"Hank Arnold" <ras...@aol.com> wrote in message
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