See http://en.wikipedia.org/wiki/Swappiness
On 13 March 2013 19:56, Fredrik Stigbäck
wrote:
> Well, we've seen a Cassandra process swap out 500 MB on a Linux OS
> with plenty of RAM, so I was just curious as why the OS thinks it
> should use the swap at all.
>
> 2013/3/13 karim duran :
> > I agr
Well, we've seen a Cassandra process swap out 500 MB on a Linux OS
with plenty of RAM, so I was just curious as why the OS thinks it
should use the swap at all.
2013/3/13 karim duran :
> I agree with Edward Capriolo,
> Even when swap is enabled on your system, swaping rarely occurs on OS
> today..
I agree with Edward Capriolo,
Even when swap is enabled on your system, swaping rarely occurs on OS
today...(except for very loaded systems).
But, take care that some 32 bits system kernels allows only 2^32 bits
memory mapped file length ( ~ 2 Go ).
It could be a limitation for NoSQL databases. It
You really can not control what the OS-swaps out. java has other memory
usage outside the heap, and native memory. best to turn swap off. Swap is
kinda old school anyway at this point. It made sense when machines had 32MB
RAM.
Keeping your read 95th percentile low is mostly about removing deviatio
I've got a question regarding understanding the recomendation to disable
swap.
Since Cassandra uses mlockall to lock the heap in RAM what is the reason
for disabling swap?
My guess is that is has to do with memory mapped files but as of my
understanding, accessing pages of
memory mapped files, t
