Multi Server Load Balancing and remember search criteria

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foosh101
Posts: 61
Joined: Tue Oct 22, 2002 2:13 pm

Multi Server Load Balancing and remember search criteria

Post by foosh101 »

In my search scripts, I use the EXPORT tag to maintain many of my search criteria between searches. This works great in my development environment, however my production environment has 3 different servers, and my tables and indexes are replicated to each one them. I then do some round robin load balancing to share the load between them. The problem I am experiencing is that it is just not working. It would seem that the the search attributes exported in my scripts are lost when the search request goes to another server. This makes sense, however what I neeed to know is: Is that what is happening, and is maintaining all the search criteria in the querystring the only way to fix the problem?
foosh101
Posts: 61
Joined: Tue Oct 22, 2002 2:13 pm

Multi Server Load Balancing and remember search criteria

Post by foosh101 »

Also, I know that using the EXPORT function is more efficient than maintaining all the search criteria in the querystring. How much more efficient is it? My search allows the user to search my tables by a number of different search attributes. I have more than 10 indexes on my table. For this reason I am actually worried about the querystring not being able to contain all the search criteria. Is it likely for me to create a querystring that is too big? Also, instead of replicating the data to all the servers, would it make more sense to partition certain portions of the data to different servers, and only hit the appropriate server when doing my queries, thus allowing me to use the EXPORT function.
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John
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Multi Server Load Balancing and remember search criteria

Post by John »

EXPORT to table is not necessarily more efficient than EXPORT to URL or QUERY. Where it gains in efficiency is if you have lots of links, the URLs will be shorter. In general you will want to keep your URLs under a few hundred bytes. If you can do that you could use EXPORT URL or QUERY.

If your data is easily partitioned to different servers and hitting the appropriate one does make sense, as each server can then cache the data it needs, which will improve performance.

Another alternative if possible with the load balancer is to keep a user on one server once assigned to one.
John Turnbull
Thunderstone Software
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