Geodatasource: number of connected threads

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kecskemetib
Posts: 6
Joined: Fri May 30, 2014 1:01 pm

Geodatasource: number of connected threads

Post by kecskemetib »

Dear Forum Members,

We have encountered something strange while using geodatasource layers with many threads of xroutemodules running. We are calling xRoute from 80 client threads, equal to the size of the module pool on 2 servers (poolsize is 40-40 each).

The database containing the geodatasource layer is a MySql database running on one of the servers.

While observing the number of open conncetions to the MySql db, we noticed that it goes up to as high as 498 threads. It seems as if xRoute is not closing the connections properly - is this a bug?

We have two additional questions:

1. How should we set the maximum number of allowed connections on the db? Let's say we set poolsize=40 on 2 xroute servers. What should be the setting for max_connections in the db? We experimented, and, if we set it below 500, then some modules will throw exceptions. Is there a general rule for the max_connections setting?

2. From a performance point of view, is it better to have the geodatasource db on the same machine as the ptv server, or a different server? We have a small, static geodata layer. Our experiments show that there isn't much difference, but is there any guidance on this?

Thanks,
Balázs
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Bernd Welter
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Joined: Mon Apr 14, 2014 10:28 am
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Re: Geodatasource: number of connected threads

Post by Bernd Welter »

Hello Balacs,

I've been in contact with Reinhard who is going to answer your posting next week (after the 1.18.1 servers have been released :D ). He said that your are not running into troubles with the current default settings but he will explain the mechanisms in detail in a dedicated answer. Please be patient,

Regards from Germany,
Bernd
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