Jianlin Lv <iecedge@xxxxxxxxx> writes: > On Sun, Oct 8, 2023 at 9:17 AM Huang, Ying <ying.huang@xxxxxxxxx> wrote: >> >> Jianlin Lv <iecedge@xxxxxxxxx> writes: >> >> > From: Jianlin Lv <iecedge@xxxxxxxxx> >> > >> > Global reclaim will swap even if swappiness is set to 0. >> >> Why? Can you elaborate the situation? > > We reproduced the issue of pages being swapped out even when swappiness is > set to 0 in the production environment through the following test program. > Not sure whether this program can reproduce the issue in any environment. > > From the implementation of the get_scan_count code, it can be seen that, > based on the current runtime situation, memory reclamation will choose a > scanning method (SCAN_ANON/SCAN_FILE/SCAN_FRACT) to determine how > aggressively the anon and file LRU are scanned. However, this introduces > uncertainty. > > For the JVM issue at hand, we expect deterministic SCAN_FILE scan to avoid > swapping out anon pages. Why doesn't memory.swap.max work? -- Best Regards, Huang, Ying