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View Full Version : what is a swap file for and do i need one?



tmontana
4th April, 2012, 09:02 PM
hey guys,

i have a quick question and cant find a clear answer online:

what is a swap file, what does it do and do i need one?

I have a VU+ duo with an attached USB stick /media/usb and a 2TB HDD fitted /media/hdd

I see there is a "swap manager" option in vix 2.3 but am clueless what its for.

hope someone can shed some light

cheers

alan

TheCoder
4th April, 2012, 09:59 PM
Swap files are special files or partitions that give the illusion of having more hardware memory (ram). The idea is that when tasks have completed their processor timeslice they are paged into the swap file thus freeing up more real memory for subsequent tasks.

The disadvantage is that disk drive access is incredibly slow in comparison to normal memory access. This can be mitigated somewhat by having a good memory manager that only pages when absolutely necessary.

Its always best to have real memory where possible but if its not then swap files/paging can provide a workable solution

tmontana
4th April, 2012, 10:05 PM
Thanks for the explanation mate

So is it recommended to create a swap file or not?


Cheers

digicon
5th April, 2012, 02:15 AM
Thecoder is spot on with that explanation, Swapfiles came about in images when the Dm500s had very little memory the same as the 800HD .

But in these days with the Duo having 384mb of ram a swap is not really needed and the later versions like the ET9200 and Ultimo now have 512mb making a swap file a thing of the past

lincsat
5th April, 2012, 03:29 AM
There are quite a few reports of Vu+ Duo's with full RAM, especially when using several EPG providers. It can be a good idea to use a swap, better on USB flash memory than HDD.

RuberDuck
13th April, 2012, 10:12 PM
Generally speaking SWAP files are not needed on modern E2 receivers and can have a rather detrimental effect on the operation of the receiver where used. saying that receivers with low memory such as the Duo or the Solo can benefit from a temporary SWAP file for use when parsing EPG data.