ADSM-L

Re: Performance Large Files vs. Small Files

2001-02-16 13:42:41
Subject: Re: Performance Large Files vs. Small Files
From: Joe Faracchio <brother AT SOCRATES.BERKELEY DOT EDU>
Date: Fri, 16 Feb 2001 10:40:28 -0800
Also what size (and how many) processors are in the Windows NT/W2K
machine???

I have seen non-server win-nt clients halve their processing time when a
user upgrades from Pentium to Pentium II or III, etc.

Client processor muscle matters!  My first Mac clients only got
25Megs/Hour!!!

                ... joe.f.

Joseph A Faracchio,  Systems Programmer, UC Berkeley


On Wed, 14 Feb 2001, Richard Sims wrote:

> >I believe you change the buffer pool size in the dsmserv.opt file and use an
> >entry as follows:
> >BUFPOOLSIZE 16384
> >The accepted way to do this is to note your current buffer pool size and then
> >double it. Watch your cache hit percentage for a day or two and then double
> >again to achieve the optimal server performance with should be attained when
> >the cache hit percentage is stable and above 99 percent...
>
> By all means pursue this.  But...as the ADSM Performance Tuning Guide pointed
> out (http://www.tivoli.com/support/storage_mgt/adsm/pubs/admanual.htm#perfV3)
> you should not do this without observing realities in your operating system.
> You can certainly achieve very high Cache Hit ratios and still have crummy
> performace - because the caching is happening in virtual storage.  We
> recently saw a posting from a customer with a 70 GB database and only 512 MB
> for the server system - a tight squeeze at best, considering all the other
> memory requirements in running a server system.  Server systems need abundant
> memory.
>
> This all boils down to capacity planning and being realistic about what can be
> achieved in the current system's configuration.  You need to consider much
> more than TSM, in that it's just one passenger demanding service on the cruise
> ship.
>
>    Richard Sims, BU
>