Boris Bakchiev
2006-Apr-11 17:19 UTC
[Asterisk-Users] Re: update - 512 Simultaneous Callswith DigitalRecording
> Are there any advantages/disadvantages to using tmpfs as opposed tothe> following method:Matt, Its simple. To quote the docs, "tmpfs lives entirely in the kernel's caches" It will shrink and grow to accommodate the files that currently on the filesystem. So if you allocate 10GB for your /tmp but only use 500MB it will only use 500MB of RAM. Think of the time your server run out space on your RAM drive... With tmpfs you would still be ok for few weeks (provided you allocated enough space). :) This will also benefit whole system if /tmp is located on tmpfs, not that a stable, production asterisk system would actually use /tmp much (if at all). In short it gives you the benefits of LARGE RAM disk without allocating all that memory beforehand and you don't have to format anything during startup. For further info look at the following link to tmpfs.txt from kernel's docs http://www.kernelhq.cc/browse-view.py?fv_nr=232372
Leo Ann Boon
2006-Apr-11 20:56 UTC
[Asterisk-Users] Re: update - 512 Simultaneous Callswith DigitalRecording
Boris Bakchiev wrote:>>Are there any advantages/disadvantages to using tmpfs as opposed to >> >> >the > > >>following method: >> >> > >Matt, > >Its simple. To quote the docs, "tmpfs lives entirely in the kernel's >caches" >It will shrink and grow to accommodate the files that currently on the >filesystem. > >So if you allocate 10GB for your /tmp but only use 500MB it will only >use 500MB of RAM. Think of the time your server run out space on your >RAM drive... >With tmpfs you would still be ok for few weeks (provided you allocated >enough space). :) This will also benefit whole system if /tmp is located >on tmpfs, not that a stable, production asterisk system would actually >use /tmp much (if at all). > >In short it gives you the benefits of LARGE RAM disk without allocating >all that memory beforehand and you don't have to format anything during >startup. > >For further info look at the following link to tmpfs.txt from kernel's >docs >http://www.kernelhq.cc/browse-view.py?fv_nr=232372 > >I'm not sure tmpfs is the right solution for the OP's problem - disk access slowing down the system. My understanding of tmpfs is that it will swap pages in and out to/from disk. Wouldn't that be as bad as directly writing to disk? I can see tmpfs will have some advantage over direct disk IO when the files are small and short-lived, i.e. less likely to be swapped. Leo