On Mon, 31 Jan 2005, Hugh Dickins said: > On Mon, 31 Jan 2005, Nix wrote: >> (2.6.10 seems to *run* perfectly well on that box, for what it's worth; >> unless this is a symptom of some underlying dark and terrible failure, >> it looks like a not-very-important cosmetic bug.) > > A lot of the time you're right and it is just cosmetic. But if memory > gets tight and it should be using swap, it mistakenly fails to do so, > so you may end up getting OOM-killed. Patch below is a temporary hack > workaround against that.
Odd: this machine seems to be using swap, albeit not very much (and I've got the swap priorities upside down, as well; whoops, that's probably been harming performance for, well, years): Filename Type Size Used Priority /dev/sda2 partition 523016 0 1 /dev/sda4 partition 511232 57648 2 /dev/sdb2 partition 523016 0 1 Is the problem that the higher-priority kicking out to swap which should happen when memory is tight, won't? > The Mapped count also affects when dirty file > writeback kicks in, but the effect there appears to be less serious. ... since it kicks in eventually anyway. > More worrying is, what else might sparc64 gcc-3.4 be getting wrong? That's a question that's very hard to answer until we know the cause of this failure and can fix it: then we can go through the RTL or assembler dumps of a kernel compilation and comb more potential problems out (or not: it's probably a long and thankless task). I'll build rmap.c with GCC-3.3 later tonight (if I can find a copy on my old backups), compare the generated code, and see if anything leaps out at me. > --- 2.6.10/mm/vmscan.c 2004-12-24 21:36:18.000000000 +0000 > +++ linux/mm/vmscan.c 2005-01-31 12:44:56.006629152 +0000 > @@ -690,6 +690,8 @@ refill_inactive_zone(struct zone *zone, > * is mapped. > */ > mapped_ratio = (sc->nr_mapped * 100) / total_memory; > + if (mapped_ratio < 0) > + mapped_ratio = 78; > > /* > * Now decide how much we really want to unmap some pages. The mapped `78'? A hack indeed! :) -- `Blish is clearly in love with language. Unfortunately, language dislikes him intensely.' --- Russ Allbery - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
