Exchange performance

anything I don't mind

anything I don't mind

anything I don't mind

Permabanned
Joined
28 Dec 2009
Posts
13,052
Location
london
What do you think is the main factor in improving exchange performance, disk iops, network latency etc ?

What about mailbox size? I have a client with 100 users and some of the users have 20gb mailboxes and some of the secretaries have access to five mailboxes over 100mbit network lan to gigabit connected exchange. Would gigabit to the client and faster exchange disk iops make a big difference or should we look at reducing mailboxes size first?

I think that new esxi hosts should be a priority as well as deleting old emails completely as they are accessible via mimecast
 
No, that is still your problem, do some due diligence and tell the clients what needs work, arrange the costings and have this written in to the contracts.

If they don't like it, move on.
 
If you don't want to answer the question then don't even bother posting.

I asked a technical question of what people thought would offer the best performance boost. I didn't ask for assistance on how to deal with a client. If i had respect for you i might have been insulted by your comment.
 
What version of Exchange is it?
What hardware is it running on currently?
Are the DBs and logs on separate arrays?
What clients are the users using?
Are you using Outlook Anywhere?
How many items do the users have in their folders?
What spec are their computers?
 
I asked myself a similar question recently groen, as our exchange 2007 sp3 was running dog slow on hyper-v for 70 clients where mailboxes were capped at 8gb.
Disk I/O was crazy high sometimes and ram usage was at 95% even though 20gb was assigned to the vm. Ensuring store.exe uses a maximum static amount helped to bring the ram consumption down.
I ended up building a new hyper-v (identical exchange install) on the same host and it's much better, thus proving a corrupt exchange install.
You didn't mention what version of exchange you are on. I'm considering upping a level in our next financial year to either 2010 or 2013.
However, it seems to me that disk I/O is hammered more than network latency. Our gigabit network doesn't seem to spike very much at all, but the disk I/O graph looks like the himalayas.
Physical hardware of the host counts for a lot, so ensure that's up to scratch first mate.
 
It was just a general question, It was not meant to be only specific to the current environment.

What version of Exchange is it?
Exchange 2003 soon to be 2010
What hardware is it running on currently?
It is on a
ESX 3.5 on hp dl385 g2 with 16gb ram. There is three hosts which connect to a netapp 2050 over iscsi. There is 15 vms across the three hosts and 100 users access them during the day. There is a physical sql server and a physical file server for the DMS store. the vmstore is not under very heavy load but it is reaching max capacity in terms of performance. We are looking to upgrade the hosts soon to hp 385 g8
Are the DBs and logs on separate arrays?
yes
What clients are the users using?
outlook 2003 soon to be 2010
Are you using Outlook Anywhere?
no
How many items do the users have in their folders?
well mailboxes range from 5-20 gb with 100 users. Some users have 100000 items+ in their mailboxes but to boost performance we tend to encourage users to move emails out of their inbox and in to sub folders at the least, this improves performance for the inbox only.
What spec are their computers?
intel i3 with 3gb ram. hp 8100 sff running windows 7.


We plan to implement mailbox size limits when we move to 2010 and the client has agreed upon this policy but it just convincing the users that they need to delete several years worth of email from their outlook is problematic. I still think that upgrading the hosts should be a priority over moving to 2010.


I should add that the exchange 2003 is currently on windows 2003 32bit with only 3gb or vram allocated. The question is if we had a strict policy and lawyers actually listened to IT and everyone mailbox was capped at 5gb would the users notice any difference on the current hardware. Basically my boss is telling the client that if users had smaller mailboxes there oulook would be much faster. I have been saying to him that i wouldn't exactly say that because i think we won't see a drastic speed increase until we move to faster hardware. I just wanted to see what your thoughts on that were.
 
Last edited:
You have people with 5-20GB mailboxes on Exchange 2003? that's pretty insane, those kind of sizes are more typical of Exchange 2010. Databases shouldn't be going above 100GB on Exchange 2003, so you would fill one of those with 5 20GB users!

You need to look at performance data from your servers to see what is being hit hardest. Check for some of the counters in this article. I know it says Exchange 2007 but a lot of this will be relevant to Exchange 2003 as well:

http://technet.microsoft.com/en-us/library/bb201689(v=exchg.80).aspx

Your main indicators will be how heavily your disks are being hit, how fast are they responding to read/writes? (LogicalDisk(*)\Avg. Disk sec/Read, LogicalDisk(*)\Avg. Disk sec/Write).

Do you have high MSExchangeIS\RPC Requests?

How high is the MSExchangeIS\RPC Averaged Latency? This is a direct measure of how fast RPC requests to the server are being processed.

I assume this counter is on Exchange 2003, but worth checking MSExchangeIS\RPC Num. of Slow Packets as well.

Moving to Exchange 2010 would allow you to dramatically cut the IOPS requirements for your users, simply put you can do a lot more with a lot less, you don't need the faster disks that you did with Exchange 2003.

I would also check your raid/disk config, do you have logs and databases on separate disks? do you have enough disks in your Raid groups to satisfy the IOPS requirements of your users?
 
HarryPainful said:
No, that is still your problem, do some due diligence and tell the clients what needs work, arrange the costings and have this written in to the contracts.
Click to expand...

Sadly it's never quite that easy.

I know for one particular services co they promised the earth to the client as they just wanted the contract.

Yes ultimately it's all down to the contract in the services environment, but the people who are managing that aspect of things are on the whole more interested in the commercial side of things.

Sorry for the crap explanation having a mental block today on getting my words out but you hopefully get the idea, yes the contract should include all that but sometimes for other reasons it doesn't.
 
Last edited:
I'd say your DL385 is severely overloaded and as you've pointed out only 3gb of ram cos you're on 32-bit Exchange.
Later versions of Exchange handle tasks much better anyway. But i'd not like to put 2007 onto a vm on that host.
 
Last edited:
Eulogy said:
Moving to Exchange 2010 would allow you to dramatically cut the IOPS requirements for your users, simply put you can do a lot more with a lot less, you don't need the faster disks that you did with Exchange 2003.
Click to expand...
Exchange 2010 loves RAM. I'd throw 64GB at it for 100 users. You can get away with less but why bother?

As already pointed out, Exchange 2003 -> Exchange 2010 results in an 'average' drop of 93% in disk IOPS. I believe 2013 will be another 50% on top of that for a 96.5% reduction. Your disks are very probably getting hammered in 2003 unless you're on a 6+ disk RAID10.
Having logs and DBs on separate arrays helps a lot with 2003, 2010 not so much.

groen said:
mailboxes range from 5-20 gb with 100 users. Some users have 100000 items+ in their mailboxes but to boost performance we tend to encourage users to move emails out of their inbox and in to sub folders at the least, this improves performance for the inbox only.
Click to expand...
These are too big. Eulogy is correct in pointing out that is too big for an Exchange 2003 IS. I'd feel queasy backing that up and restoring it given how incredibly fussy it is about corrupt files.

Keeping the number of items in Inbox, Sent Items, Calendar etc. under 1,000 really helps performance in Outlook 2003, I'd say up to 5,000 items per subfolder for filing purposes.
Exchange 2010 + Outlook 2010 has online archives which are very nice for 'dealing with' these really bloated users. I don't see why you need more than 10GB in a mailbox though, it's not a storage or filing system, it's just email.

groen said:
Basically my boss is telling the client that if users had smaller mailboxes there oulook would be much faster. I have been saying to him that i wouldn't exactly say that because i think we won't see a drastic speed increase until we move to faster hardware. I just wanted to see what your thoughts on that were.
Click to expand...
I'd be inclined to agree with your boss. 2003 was not built for what they're doing with it. Upgrading the host machines (which look fine spec wise) will be ****ing in the wind without getting a grip on these issues.
 
OK thanks. Either way we need to deal with the massive mailboxes but i was just not sure if we should do the hosts first, before exchange/office 2010 and reducing mailboxes. But after what you have said i think reducing mailboxes as a priority and moving to 2010 and then upgrading hosts will be ok.
 
I think i'd be looking to build the new 2010 exchange asap. Get the users to reduce their mailbox size, show them how easy archiving is and if you save the archives to another hdd/array whatever then you can migrate much smaller mailboxes over when you're ready to. THEN apply mailbox storage quotas going forward.
 
Banzai_Joe said:
then you can migrate much smaller mailboxes over when you're ready to. THEN apply mailbox storage quotas going forward.
Click to expand...

Indeed - I expect migrating 20GB mailboxes could be a pain as the corrupt item count might have to be quite big to get them to move...
 
Just FYI, I've got a Exchange implementation planned for the new year and there are many tools to allow for performance testing from MS, so if you're doing an upgrade to 2010, make sure you use them before it goes live.

I'd also look at some sort of archiving solution, like many have said, those mailboxes are too big.
 
We use mimecast which works as a spam filter, archive and even DR solution. But that means people have to a) learn how to use it b) go through the extra effort of not having it in their outlook. There is a mimecast outlook plugin but it conflicts with other addons and slows down outlook. The system runs ok though, it is not slow enough for me to moan about it. Since we put new desktop in i think it runs pretty fast, but they have to understand if they click on a sub folder with 20000 items in it and they have not clicked it on for a while. Outlook is going to take a few seconds to load the emails if cached exchange mode is not on. But you get some users who always moan. There is also internal politics about the problem. IT ends up having to go in to each mailbox and manually pst old mailboxes. But we can't do that during the day or it slows down exchange.
 
You must log in or register to reply here.
Back
Top Bottom