Re: [PATCH 4/4] maps: /proc/<pid>/pmaps interface - memory maps in granularity of pages

Matt,

It's not easy to do direct performance comparisons between pmaps and
pagemap/kpagemap. However some close analyzes are still possible :)

1) code size
pmaps                   ~200 LOC
pagemap/kpagemap        ~300 LOC

2) dataset size
take for example my running firefox on Intel Core 2:
VSZ             400 MB
RSS              64 MB, or 16k pages
pmaps            64 KB, wc shows 2k lines, or so much page ranges
pagemap         800 KB, could be heavily optimized by returning partial data
kpagemap        256 KB

3) runtime overheads
pmaps            2k lines of string processing(encode/decode)
kpagemap        16k seek()/read()s, and context switches (could be
                    optimized somehow by doing a PFN sort first, but
                    that's also non-trivial overheads)

So pmaps seems to be a clear winner :)

Thank you,
Fengguang

-
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/

---

• References:
  • Re: [PATCH 4/4] maps: /proc/<pid>/pmaps interface - memory maps in granularity of pages
    • From: Matt Mackall <[email protected]>

• Prev by Date: Re: [PATCH 0/24] make atomic_read() behave consistently across all architectures
• Next by Date: Re: [PATCH] autofs4: deadlock during create
• Previous by thread: Re: [PATCH 4/4] maps: /proc/<pid>/pmaps interface - memory maps in granularity of pages
• Next by thread: Re: [PATCH 4/4] maps: /proc/<pid>/pmaps interface - memory maps in granularity of pages
• Index(es):
  • Date
  • Thread

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]