Running Concurrent SQL statements

#1

I've noticed when you run numerous sql statements at the same time, it
takes longer for the statements to finish than if they ran alone. It
seems that the server only runs one sql statement at a time. Is there
some way to change this so the server can run multiple statements at
the same time, or is this a limitation of Pervasive.SQL? I'm running
Pervasive.SQL v8 on a Windows 2000 server.

#2

smpete33 (AT) gmail (DOT) com wrote:

Quote:

I've noticed when you run numerous sql statements at the same time, it
takes longer for the statements to finish than if they ran alone. It
seems that the server only runs one sql statement at a time. Is there
some way to change this so the server can run multiple statements at
the same time, or is this a limitation of Pervasive.SQL? I'm running
Pervasive.SQL v8 on a Windows 2000 server.

Are they big, long running queries? How many records does each query
need to scan? It's quite possible that by running them at the same time
you're running out of cache memory and/or disk I/O bandwidth.

Guy
-- --------------------------------------------------------------------
Guy Dawson I.T. Manager Crossflight Ltd
gnues (AT) crossflight (DOT) co.uk

#3

No, they are not long running queries. Most take less than 1 second to
run with the longest taking 3 seconds. I have tested this on a server
where this process is the only thing running and I still see the same
problem. When I run the process twice at the same time, the individual
sql statements still take the same time to run, but in whole the whole
process takes longer. That's why it seems Pervasive isn't running more
than one sql statement at a time.

#4

smpete33 (AT) gmail (DOT) com wrote:

Quote:

No, they are not long running queries. Most take less than 1 second
to run with the longest taking 3 seconds. I have tested this on a
server where this process is the only thing running and I still see
the same problem. When I run the process twice at the same time, the
individual sql statements still take the same time to run, but in
whole the whole process takes longer. That's why it seems Pervasive
isn't running more than one sql statement at a time.

How many "REAL" CPU's are there on the server?

#5

Dual 2.8 Ghz processors
2 Gb RAM
RAID - 1 mirrored 72 Gb drives w/ online spare

#6

smpete33 (AT) gmail (DOT) com wrote:

Quote:

No, they are not long running queries. Most take less than 1 second to
run with the longest taking 3 seconds. I have tested this on a server
where this process is the only thing running and I still see the same
problem. When I run the process twice at the same time, the individual
sql statements still take the same time to run, but in whole the whole
process takes longer. That's why it seems Pervasive isn't running more
than one sql statement at a time.

I know our installation (P.SQL V8.6 on Netware V5.1 SP8) runs multiple
SQL statments because I can run a mix of long (minuits), medium (seconds)
and short (sub second) queries at the same time along with lots of users
accessing the database via both Btrieve ans P.SQL.

Have you any idea how much data each query scan? I'm still wondering if
the disks and/or cache are a bottlneck.

Guy
-- --------------------------------------------------------------------
Guy Dawson I.T. Manager Crossflight Ltd
gnues (AT) crossflight (DOT) co.uk

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Running Concurrent SQL statements

comp.databases.btrieve comp.databases.btrieve

Running Concurrent SQL statements - 10-21-2005 , 04:41 PM

Re: Running Concurrent SQL statements - 10-24-2005 , 07:34 AM

Re: Running Concurrent SQL statements - 10-24-2005 , 08:54 AM

Re: Running Concurrent SQL statements - 10-24-2005 , 11:16 AM

Re: Running Concurrent SQL statements - 10-24-2005 , 01:30 PM

Re: Running Concurrent SQL statements - 11-01-2005 , 09:56 AM