2008/8/24 John McCabe-Dansted <[EMAIL PROTECTED]>:> > The size of the virtual swap drive will be 150% of physical RAM. I.e. > if you have 1GB of ram it will be 1.5GB. However each 4k page will > only take 2k of memory when compressed (assuming 2:1 compression), so > when the swap device is full it will only require 0.75GB of physical > memory to store the contents of the 1.5GB swap device. > > Assuming a 2:1 compression ratio there is clearly no point allocating > a 200% of RAM swap device. Also note that the size of the swap device > is limited to 4GB. Also on 32bit systems, the total amount of memory > that kernel modules can allocate is 1GB so using 2GB swap device would > be pointless no matter how much ram the system has (and could > potentially cause the kernel to run out of memory). > > Since compcache does not allocate memory until it is needed, for a > short running system it is best to specify a slightly too large swap > device than a too small. OTOH compcache-0.3 cannot really free memory > (except when the module is unloaded from the kernel with e.g. > unuse_compcache), so in a long-running system it may be better to have > a smallish compcache. This would force the OOM killer to kill runaway > processes before compcache allocates too much memory. > > -- > John C. McCabe-Dansted > PhD Student > University of Western Australia >
-- John C. McCabe-Dansted PhD Student University of Western Australia ------------------------------------------------------- Thank you for exlanation, very usefull, BTW I modified your script to be "compatible" with arch linux scripts. Everyone who want to install compcache on arch linux, please look to aur. Tibor
compcache.v2
Description: application/shellscript
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