On 4-26-14 09:43:41 Heinz Diehl wrote: > On 26.04.2014, Garry T. Williams wrote: > > That's not true. Swap will come into play and unreferenced data > > in the /tmp files will be paged out in favor of claiming that > > memory for other uses. > > Did you actually try? > > [htd@kiera ~]$ dd if=/dev/zero of=/tmp/bigfile bs=1M count=3000 > dd: error writing ‘/tmp/bigfile’: No space left on device > 2048+0 records in > 2047+0 records out > 2147450880 bytes (2.1 GB) copied, 0.920556 s, 2.3 GB/s > > [htd@kiera ~]$ free -m > total used free shared buffers cached > Mem: 3745 1562 2183 0 0 773 > -/+ buffers/cache: 787 2957 > Swap: 8191 0 8191 > > I have 4 GB of memory in my machine, and mount defaults to > "size=50%" (= 2GB). I have been running /tmp as a tmpfs a long time, > because the harddisk is a SSD. What happens can you see above: it > creates a 2 GB file and aborts for the next 1 GB. The machine has 8 > GB of swap, and nothing of it was used.
When another process requires memory in excess of what is immediately available, the unreferenced file(s) in /tmp can be paged out to accommodate the request. If memory pressure is absent, no paging will occur. There is no pressure here. (I only wanted to correct the claim that placing files in /tmp would encumber main memory to the detriment of other processes. That is not so as long as the system can page out unneeded memory.) > Disclaimer: this is not a rant against having /tmp using tmpfs. I'm > aware of the limitations, and have only encountered positive > experiences so far. This is my experience, too. -- Garry T. Williams -- users mailing list users@lists.fedoraproject.org To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
