Forum OpenACS Development: Re: cache statistics

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4: Re: cache statistics (response to 1)
Posted by Dave Bauer on
Malte,

You can get a general idea of the size of the NSVs just by calculating the total string lengths of it, but obviously it won't be perfect. In general I think the NSVs are not that big, Jeff did some calculations before and it was not that much.

If minthreads is < maxthreads you are killing and restarting threads while the server is running, and that will increase your RAM consumption steadily. Make them equal.

I seriously doubt you need 40 threads for 35 concurrent users anyway, but only testing could prove that.

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5: Re: cache statistics (response to 4)
Posted by Rocael Hernández Rizzardini on
Equal min and max threads leads us to continuos reboots (aolserver dying), probably due threads that never die that had errors on it.
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9: Re: cache statistics (response to 5)
Posted by Dave Bauer on
Rocael, continuous as in immediate reboots? How often? Do you need to reboot it manually, or does it crash and restart?

As far as I know, you should ALWAYS use maxthreads == minthreads and that has been the "official" advice for a very long time.

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10: Re: cache statistics (response to 9)
Posted by Rocael Hernández Rizzardini on
Dave, I don't think that applies any longer. Any intensively used site will see crashes if you set them equal, how often is variable, but no more than one hour usually. We have threadtimeout set to 1200.
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12: Re: cache statistics (response to 10)
Posted by Dave Bauer on
Rocael,

What version of AOLserver are you using.

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13: Re: cache statistics (response to 12)
Posted by Rocael Hernández Rizzardini on
4.0.10 branch.
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6: Re: cache statistics (response to 4)
Posted by Malte Sussdorff on
Dave said:

I seriously doubt you need 40 threads for 35 concurrent users anyway, but only testing could prove that.

My assumption was I should calculate one thread per concurrent user and have a little bit of space for externals that access the site occasionally. Wrong?

How could I test this?

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7: Re: cache statistics (response to 6)
Posted by Patrick Giagnocavo on
Well, one way to test it would be to calculate how long a page takes to be generated. For instance, 10 threads which serve pages that are generated in 0.5 seconds can thus serve 20 pages per second.

However, on top on that, you have the fact that most users take a while to read each page. So, you need to calculate page loads per minute.

So our 10 threads above can serve 20 pages per second * 60 = 1200 pages per minute. If you have longer page generaton times, you need to adjust accordingly.

The most threads I have seen on any server is 35 threads. This application served some 20,000 to 35,000 users per week doing a multistep data entry/questionnaire application.