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Computer Software => Linux => Topic started by: Chrysalis on July 09, 2014, 03:17:35 PM

Title: 64 bit linux (debian) 96gig limit
Post by: Chrysalis on July 09, 2014, 03:17:35 PM
Have a box hosting some stuff, has 192gig of ram.

The OS see's all the ram.  However it will only use half of the ram, the 2nd half just sit unallocated, cache, userspace apps etc. wont use it.  When half of the ram is in use swap takes over.

Anyone know of some kind of 96gig linux bottleneck? or a scenario that would cause linux to recognise ram but not use it?
Title: Re: 64 bit linux (debian) 92gig limit
Post by: roseway on July 09, 2014, 03:43:25 PM
It might be a function of the swappiness setting. Have a look at this: http://askubuntu.com/questions/103915/how-do-i-configure-swappiness
Title: Re: 64 bit linux (debian) 96gig limit
Post by: Chrysalis on July 09, 2014, 04:04:40 PM
I will adjust it, but I do appear to have hit a hard cap.
Title: Re: 64 bit linux (debian) 96gig limit
Post by: loonylion on July 09, 2014, 04:10:23 PM
if it was 32bit using PAE I could understand it, but native 64bit shouldn't have a problem with that much ram. There's definitely no 32bit code anywhere?
Title: Re: 64 bit linux (debian) 96gig limit
Post by: boost on July 09, 2014, 04:21:40 PM
How are you trying to use it all?
Title: Re: 64 bit linux (debian) 96gig limit
Post by: Chrysalis on July 10, 2014, 05:00:51 AM
It isnt capped, I ran some test apps to force higher utilisation.

I have now adjusted swappiness down to 10 from the default as swapping out when 90gig of ram is free is stupid, so will see how it goes from now.