Am 02.06.2012 19:24, schrieb Gregory Maxwell:
Tmpfs just has the advantage of minimizing the disk activity— both
in
cases where none is needed, and in cases where it is.
you refuse to understand if some app creates a 2 GB
file in /tmp and does not remove your only pressure
is to the page-cache which is not the same as start
swapping because memory pressure
Really, you should try it. It works very well and does not
make your machine perform poorly, even when under memory
pressure
it have used tmpfs probably long before you even knew it
exists (on some workloads even for /tmp) but it is not
the holy grail for each workload and so a wrong DEFAULT
Am 02.06.2012 19:25, schrieb Chris Adams:
Once upon a time, Reindl Harald <h.reindl(a)thelounge.net> said:
> Am 02.06.2012 04:08, schrieb Jesse Keating:
>> The useless 2G file will get swapped out, not important things that are actively
being used in ram
>
> it does not matter WHAT get swapped out
> from the moment on the system starts to swap performance sucks
With /tmp-on-storage, that 2G file would have already caused a large
amount of I/O; it is the same 2G being written on to the same storage,
whether a /tmp filesystem or swap
you refuse to understand the difference WHEN this happens
writing 2 GB to disk on modern fileystems is meaningless
having the 2 GB in memory and a by the introduced memory
pressure swapped out application get the focus and allocate
a large amount of memory while loading large data you have MULTIPLE
pressure
* relaod the application form swap
* load application data from disk
* write /tmp and/or other data to disk
so you have THREE heavy disk usage patterns with
mixed read and write - have fun with your coffee
again: there may be workloads where it is nice and a small
improvement as i have some of them by my self but that does
NOT qulify it as a os-wide default