Ubuntu 16.04: “Out of memory” errors after upgrade to 4.4.0-59

Re:Ubuntu 16.04: “Out of memory” errors after upgrade to 4.4... by mrmondo on Sunday January 29, 2017 @04:56AM (#13513393)

yes, we run ZRAM of every single server we have, its fantastic and we don't have swap anywhere. It's worth noting though that vm.swappiness is set to 0 then ZRAM wont be used, it must be set to 1 or higher unless you're using a really old kernel (pre 3.5).

[ Parent | on HN ]

Re:Ubuntu 16.04: “Out of memory” errors after upgrade to 4.4... by fpoling on Monday January 30, 2017 @05:41PM (#13525786)

I have found that zswap behaves much better than zram when the size of the used ram approaches 150% of RAM. In theory zram compresses better as zswap has very simple mapping for the location of its cache of compressed pages leading to space underutilization. But, as it has real backing store, it can evict unused pages allowing bigger chunk of uncompressed memory for running applications.

[ Parent | on HN ]

Re:Ubuntu 16.04: “Out of memory” errors after upgrade to 4.4... by mwpmaybe on Sunday January 29, 2017 @07:43AM (#13513868)

zram[0] is not the same thing as zswap[1].

0. https://en.wikipedia.org/wiki/Zram

1. https://en.wikipedia.org/wiki/Zswap

[ Parent | on HN ]