Re: [gentoo-user] tmp on tmpfs

On 17-05-24 at 05:34, Rich Freeman wrote:
[..]
> Others have mentioned zram.  I've used it, but unless something has
> changed one of its limitations is that it can't give up memory.  That
> is less of an issue if you're using swap since it can be swapped out
> if idle.  However, if you're not using swap then you're potentially
> giving up a chunk of RAM to do it, though less RAM than a tmpfs if it
> is full most of the time (which I doubt is typically the case).
Seems to work fine here (with kernels newer than the late 3.x when I started using zram):

radiocarbon:~% dd if=/dev/urandom of=/tmp/foo
^C3405370+0 records in
3405370+0 records out
1743549440 bytes (1.7 GB, 1.6 GiB) copied, 10.8268 s, 161 MB/s
dd if=/dev/urandom of=/tmp/foo  8 MiB 10.853 (user: 0.339, kernel: 10.482)
radiocarbon:~% zramctl
NAME       ALGORITHM DISKSIZE  DATA COMPR TOTAL STREAMS MOUNTPOINT
/dev/zram0 lz4             2G    4K   64B    4K       8 [SWAP]
/dev/zram1 lz4             3G  1.6G  1.6G  1.6G       8 /tmp
radiocarbon:~% free -m
              total        used        free      shared  buff/cache   available
Mem:           7920        3096          61         228        4763        4487
Swap:          2047           0        2047
radiocarbon:~% rm /tmp/foo
radiocarbon:~% zramctl
NAME       ALGORITHM DISKSIZE  DATA COMPR TOTAL STREAMS MOUNTPOINT
/dev/zram0 lz4             2G    4K   64B    4K       8 [SWAP]
/dev/zram1 lz4             3G  3.9M    1M  1.3M       8 /tmp
radiocarbon:~% free -m
              total        used        free      shared  buff/cache   available
Mem:           7920        1412        3458         229        3049        6171
Swap:          2047           0        2047

-- 
Simon Thelen