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Article Cache Limit: how many articles equals 150mb? [solved]

Posted: February 20th, 2008, 5:46 pm
by DeXeS
Hello,
I red on the forum that probably the best to set the article cashe limit is at least 1 full 50mb plus a little more but its better to do 2 plus some more so I would like to limit it to 155 mb but how do I do this?
Because the limiter is in "articles" but 1 article can sometime in a rare situation be up to 10 mb but also 128 kb  ??? ???. How do I limit it to 155mb?


For if its needed:
Version: 0.3.1 Final
OS: Ubuntu 7.10 Gutsy Gibbon
Install-type: python source

Re: Article Cache Limit: how many articles equals 150mb?

Posted: February 20th, 2008, 5:55 pm
by switch
How much RAM do you have? Unless SABnzbd is running on a system with 128MB of RAM or lower, I suggest you just keep article cache as the default value (0). SABnzbd will only use what is needed.

Re: Article Cache Limit: how many articles equals 150mb?

Posted: February 20th, 2008, 6:43 pm
by DeXeS
Thanks! ;D

Re: Article Cache Limit: how many articles equals 150mb?

Posted: February 21st, 2008, 3:36 am
by shypike
The only function of the article cache is to prevent individual articles from being written disk. The idea is to keep the articles in memory until they can be assembled into the file they belong to. Otherwise each article would be written to disk twice, once as an individual article and once as part of its file.
You only need memory as much as is needed to keep all articles of one file in memory, plus a bit more because downloading and writing files to disk overlaps.
If you allocate too much memory, the operating system will start disk-swapping, which negates the advantage of the article-cache.

So on low-memory systems, keep the cache 0.
On high-memory systems, you can even set it to -1, which is unlimited. In reality no more than 1.5 times the largest file is used.
You set a limit in config->general, by setting e.g. to 155M.

BTW an article is unlikely to be 10MB, I think it won't make it to all Usenet servers.
Files can have an arbitrary size, because they consist of multiple articles.

Re: Article Cache Limit: how many articles equals 150mb?

Posted: February 21st, 2008, 1:34 pm
by DeXeS
So... How do I fill in this function if I want it to max use 155MB? Like "155M" or "155" or "155MB" or "155000kb" or "155000"

My server pc is a pentium 3, 866mhz 512MB of ram and the only thing this server pc does is run ubuntu server 7.10, SABnzbd+ and Samba share for my personal NAS so no huge stress on the memory or hard disk.

the second question; is 155mb actually the best setting? or would -1 (unlimited) be better in my situation?

and, Shypike, what do you mean with this:
If you allocate too much memory, the operating system will start disk-swapping, which negates the advantage of the article-cache.
I thought that the more memory, the better sab runs?

Re: Article Cache Limit: how many articles equals 150mb?

Posted: February 21st, 2008, 2:51 pm
by shypike
Choose to spell it complely in digits or use the K or M or G or T or P suffix.
155M = 162529280
There is a Wiki site explaining this. Just click on Help in the Config->Switches page.

The only reason SABnzbd is faster with cache is that it prevents unnecessary writing to disk.
When the memory cache is being swapped to disk by the operating system (because it is too large),
this purpose is defeated!
You have to experiment with the value to get the best result for your particular situation.

Re: Article Cache Limit: how many articles equals 150mb?

Posted: February 21st, 2008, 4:39 pm
by DeXeS
shypike wrote: Choose to spell it complely in digits or use the K or M or G or T or P suffix.
155M = 162529280
Thanks for explaining this.
shypike wrote: There is a Wiki site explaining this. Just click on Help in the Config->Switches page.
There is indeed but nothing about the cache limit that I can find (except "Enable periodic save")
how stupid  :o :o compleetly looked over that. found it on the general page  :o

Re: Article Cache Limit: how many articles equals 150mb?

Posted: February 21st, 2008, 5:01 pm
by shypike
OK, it's Config->General (hit the Help button on this config page then).

http://sabnzbdplus.wiki.sourceforge.net ... re+General

Even more info:
http://sabnzbdplus.wiki.sourceforge.net/High+speed

Re: Article Cache Limit: how many articles equals 150mb?

Posted: February 22nd, 2008, 12:39 pm
by nzb_leecher
On my pc the articles are around 250kb