Performance Tuning TDP domino

[Xeroid]

Hi,

I was wondering if the tcpbuff and tcpwinsize had an effect on the backup or on the restore process?

I thought it was on backup, but now I have read that the tcp/ip protocoll requests its windowsize of the receiver and does not go above the value that is set for tcpwinsize on the receiver of the data.

Could anyone confirm this and/or explain me a bit better?

Thanks!

Xeroid

 

[terlisimo]

Hello...

I never needed to tune TCP parameters for domino since usually disk was the bottleneck. Are you sure you need to experiment with TCP options? Usually this is only required when backing up a large number of small files. Domino mailboxes are usually large enough so that any change in TCP parameters won't have much impact on performance.

However, it did help for me to increase TDP disk read buffers... this is what I have in my domdsm.cfg:


BUFFers 8
BUFFERSIze 8192
SESSions 2


You'll notice that I increased Sessions parameter to 2. Basically, this means the TDP client spawns two processes that read/send data to TSM server. Since I'm using client compression, CPU became the bottleneck for me. This way two CPU cores are utilized for compressing data instead of just one.

 

[terlisimo]

By the way... test your TSM server <-> Client network transfer rate using FTP or a similar tool.

What platforms is your domino/tsm running on? I'm using Win clients and Linux server and everything works pretty well with default TCP values... TDP gives me around 90MB/s on 1Gig ethernet.

If your server is on AIX maybe you'll need to tune it to get maximum performance.

 

[Xeroid]

Hi,

I have tsm on win 2008 and domino server is win 2003. I am having bad performance regarding backup and restore. It is between 6 and 25 MB/S. I need to figure out what the bottleneck is, that is why I was playing around with these values, but I guess that it does not have an effect on the backup.
It can still be network related, or the I/O on the NAS( it is actually a virtual server). I am currently testing also the buffer and buffersizes and have set the option statistics=yes.
I did some robocopy test with a file outside TSM to see what the rate would be. I had +- 100MB/S going from TSM to domino(and others), but back from domino to tsm it showed the same as when doing backups(so 25 max).
I am still wondering what it will be. I have contacted our NAS expert, if he does not find something, it will be the network guy

Thanks for your reply!

 

[Xeroid]

Hi,

I found this in the documentation of TSM:

The TCPWINDOWSIZE server option specifies the amount of receive data in kilobytes that can be on a TCP/IP connection at one time. The TCPWINDOWSIZE server option applies to backups and archives. The TCPWINDOWSIZE client option applies to restores and retrieves.

Regards
Dennis