lkml.org 
[lkml]   [2007]   [Mar]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [RFC][PATCH 3/7] Data structures changes for RSS accounting
    Date
    Pavel Emelianov <xemul@sw.ru> writes:

    > Adds needed pointers to mm_struct and page struct,
    > places hooks to core code for mm_struct initialization
    > and hooks in container_init_early() to preinitialize
    > RSS accounting subsystem.

    An extra pointer in struct page is unlikely to fly.
    Both because it increases the size of a size critical structure,
    and because conceptually it is ridiculous.

    If you are limiting the RSS size you are counting the number of pages in
    the page tables. You don't care about the page itself.

    With the rmap code it is relatively straight forward to see if this is
    the first time a page has been added to a page table in your rss
    group, or if this is the last reference to a particular page in your
    rss group. The counters should only increment the first time a
    particular page is added to your rss group. The counters should only
    decrement when it is the last reference in your rss subsystem.

    This allow important little cases like glibc to be properly accounted
    for. One of the key features of a rss limit is that the kernel can
    still keep pages that you need in-core, that are accessible with just
    a minor fault. Directly owning pages works directly against that
    principle.


    > diff -upr linux-2.6.20.orig/include/linux/mm_types.h
    > linux-2.6.20-0/include/linux/mm_types.h
    > --- linux-2.6.20.orig/include/linux/mm_types.h 2007-02-04 21:44:54.000000000
    > +0300
    > +++ linux-2.6.20-0/include/linux/mm_types.h 2007-03-06 13:33:28.000000000 +0300
    > @@ -62,6 +62,9 @@ struct page {
    > void *virtual; /* Kernel virtual address (NULL if
    > not kmapped, ie. highmem) */
    > #endif /* WANT_PAGE_VIRTUAL */
    > +#ifdef CONFIG_RSS_CONTAINER
    > + struct page_container *rss_container;
    > +#endif
    > };
    >
    > #endif /* _LINUX_MM_TYPES_H */

    Eric
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2007-03-11 20:17    [W:0.021 / U:2.360 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site