Icon View Thread

The following is the text of the current message along with any replies.
Messages 1 to 6 of 6 total
Thread Performance in 4.35
Wed, Mar 6 2013 12:36 PMPermanent Link

Shane McCall

Tim,

Could you elaborate a bit on what the performance enhancement was for
4.35 and what kind of performance increases you saw in testing for large
queries? Also - is this an improvement with benefits for C/S only,
fileserver only, or both. Win Vista/7/8/SMB2 only or XP also. Trying to
decide if I should back port the change or just introduce it as part of
the normal development cycle for a handful of customers that are seeing
performance issues due to the size of their databases. (Note - as we
have discussed via email - the performance issues are not a DBISAM issue
- the tables are still optimized for paradox and need to be partially
redesigned to work better with the way DBISAM selects records).

Thanks,

Sean
Thu, Mar 7 2013 11:19 AMPermanent Link

Tim Young [Elevate Software]

Elevate Software, Inc.

Avatar

Email timyoung@elevatesoft.com

Sean,

<< Could you elaborate a bit on what the performance enhancement was for
4.35 and what kind of performance increases you saw in testing for large
queries? >>

It changes the way that DBISAM opens files via the Windows API.  The
performance increases that I saw were minutes down to seconds on 2nd and
subsequent executions of a query on large tables.  This effect is visible
even beyond process termination/restart due to the fact that it's the
Windows file system doing the better caching.  The issue with the previous
DBISAM versions was that the file open call parameters were defeating any
file system caching in Windows.

< Also - is this an improvement with benefits for C/S only, fileserver only,
or both. Win Vista/7/8/SMB2 only or XP also. >>

It will benefit direct local access only, although it may help a little with
network access.

If you have any other questions, please let me know.

Tim Young
Elevate Software
www.elevatesoft.com
Thu, Mar 7 2013 3:34 PMPermanent Link

Shane McCall

Thanks for the info. Sounds like it may help with large local on-disk
temporary tables too.

-Sean

Tim Young [Elevate Software] wrote:
> Sean,
>
> << Could you elaborate a bit on what the performance enhancement was for
> 4.35 and what kind of performance increases you saw in testing for large
> queries? >>
>
> It changes the way that DBISAM opens files via the Windows API.  The
> performance increases that I saw were minutes down to seconds on 2nd and
> subsequent executions of a query on large tables.  This effect is
> visible even beyond process termination/restart due to the fact that
> it's the Windows file system doing the better caching.  The issue with
> the previous DBISAM versions was that the file open call parameters were
> defeating any file system caching in Windows.
>
> < Also - is this an improvement with benefits for C/S only, fileserver
> only, or both. Win Vista/7/8/SMB2 only or XP also. >>
>
> It will benefit direct local access only, although it may help a little
> with network access.
>
> If you have any other questions, please let me know.
>
> Tim Young
> Elevate Software
> www.elevatesoft.com
Fri, Mar 8 2013 11:03 AMPermanent Link

Tim Young [Elevate Software]

Elevate Software, Inc.

Avatar

Email timyoung@elevatesoft.com

Sean,

<< Thanks for the info. Sounds like it may help with large local on-disk
temporary tables too. >>

Yes, it will.

Tim Young
Elevate Software
www.elevatesoft.com
Mon, Mar 11 2013 5:48 PMPermanent Link

Adam H.

Good Morning Tim,

My goodness – what did you do with DBISam 4.35?!!?  You've added a super
charger to the engine I'm sure!

I’ve just tried running that restructure routine on one of the servers
we were having issues with (the server with the low RAM that took over
45 minutes to run the operation, where on other machines it took only 1
minute), and it flew through it. Well – it still took 4 minutes to
complete compared to my local computer – but that is a huge difference
in performance to what it was - especially considering the server is
under-spec'd.

Thank you very much!!! I'm looking forward to rolling this out at sites
with half decent servers as well to see if there is much performance
gain. All I can say is WOW!

Cheers

Adam.
Tue, Mar 12 2013 4:03 PMPermanent Link

Tim Young [Elevate Software]

Elevate Software, Inc.

Avatar

Email timyoung@elevatesoft.com

Adam,

<< My goodness – what did you do with DBISam 4.35?!!?  You've added a super
charger to the engine I'm sure! >>

It's just a simple flag for Windows.  The downside is that Windows uses more
memory for file caching, but nowadays this is only an issue if you've got
really huge database tables that are larger than the amount of memory on
that machine *and* you do something that affects the entire table like an
optimize/restructure.

Tim Young
Elevate Software
www.elevatesoft.com
Image