Best block size

#11

"Jim Moseley" <jmose (AT) mapson (DOT) attglobal.net> wrote

Quote:

"Steven Green" <greens (AT) diamondsg (DOT) com> wrote:
1) Is there any disadvantages with using a larger block size?

no

Steven,

I'd have to disagree with you. On a network, whenever you open a table,
you will get 8 blocks of data. This seems to be for speeding up
sequential
processing. But, if you are doing random reads via qLocate() then you are
forcing a lot of wasted network traffic.

I thought the same as you until my network users started screaming. After
using the Ethereal Network Monitor (a great product, btw), I found all the
wasted network traffic. My tables had 4kb blocks and I switched them to
16kb blocks, and the system couldn't keep up with the network traffic.

Sorry about my dumb question, but I am not sure of the consequence here. Did
the 16kb blocks actually work better but the network didn't get the data
through, or - I mean, do you reccommend low or high block size?

Bjorn

#12

Bjorn,

My system didn't work with a 16kb block size. Too many packets were being
retransmitted by the network, so it could never keep up.

I'm not saying not to use 16kb, just be very sure that you have optimized
every access to the table.

For my tables that were filling up, I found it was easier to archive the
oldest data to a copy of the table and keep as few records as possible in
the 'live' table.

Also, this highlighted some inefficient code that I've since fixed (which
I guess is a good thing!).

Thanks,
Jim Moseley

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Best block size

comp.databases.paradox comp.databases.paradox

Re: Best block size - 09-12-2006 , 03:28 PM

Re: Best block size - 09-15-2006 , 01:49 PM