Subject Re: Performance Problem with BOLBs??
Author ggroper

Thanks for the input.

I am using a remote host that is using Win 2000 server, and FB 1.52
classic. I do not know their detail configuration settings.

What client program are you using?? Delphi? and if so what compoonent
Are you retreving multiple Blobs at a time or only one? Mine are
short plain text message that will require RTF formating so I need to
put them in Blobs for infopower to get them. Average about 50
characters per Blob.

I have done some more testing and the problem looks more complex,
possibly a combination of Delphi and Firebird.

Using dbExpress componets with OLEDBExpress driver and FB's ODBC I can
get the time down from 30 to 7.9 sec with Blobs and 1.71 seconds with
out Blobs. The Borland IB dbExpress driver takes 30 seconds with
Blobs(and so does a FB third pary driver) and 1.18 seconds without
Blobs. I tried FIBPlus to Client Data Sets and it took 8.7 seconds
with Blobs and 1.54 seconds with out blobs, about a second less with
out client data sets.

The worst time on a local connection was 0.37 seconds with Blobs and
0.07 seconds without blobs.

Even an 8 second response time is not good enough to read 35 records???

Maybe there is some harware problem in the loop?? I'm going to see if
I can set up a test with mySQL and MS SQL Server.

Thanks for the help,


--- In, Rajesh Punjabi <rajesh@i...>
> Hi Austin,
> I use blobs to store resumes in Firebird. I have currently about 95,000
> of those and they can each go upto a 4-5 page word document each. I
> experienced problems only when I try to query something inside my blob,
> not otherwise. Whether I fetch a blob field or not in the select list
> has not yet presented a problem.

> What is your server config. What is the swap space setting. Are u using
> XP or some other server OS. Can u put out the plan on your query as
> I use RH8 Linux and have had a problem with swap space sometimes.
> Whenever I start running low on physical ram or swap space FB tends to
> slow down considerably. Just my 2 bits.
> Regards,
> RP
> ggroper wrote:
> >Pete,
> >
> >My weakest Link is my cable modem, fast
download but slower upload. I
> >believe I read that it's around 150kb upload and 500kb download??
> >
> >For 3,000 charcters this can not account for the Blob performace
> >problem. (2 sec local and 30 second remote??)
> >
> >Is Firbird requesting every blob separately and waits to request the
> >next blob after it receives the first, thus sending 35 separate read
> >requests like running 35 queries - so it takes about a second for a
> >turn around?? Why so fast local and so slow remote??
> >
> >Austin
> >
> >
> >
> >