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Wawrzek

Wawrzek

  • Linux.com Member
  • Posts: 5
  • Member Since: 05 Nov 09
  • Last Logged In: 20 May 13

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  • Wawrzek
    RE: Sendfile and memory cache
    I got confirmation that the reason of above issue is memory allocation limit in 32-bit kernel (as expected).
    Link to this post 07 Nov 09

    I got confirmation that the reason of above issue is memory allocation limit in 32-bit kernel (as expected).

  • Wawrzek
    RE: LaTeX - Why and for what?
    I wrote bofh of my MSc and PhD theis in LaTeX (as well some scientific paper) and many presentation, however, it's not so popular among chemists. I also have my CV written in LaTeX. It's nice because gives special and fresh look and feel. http://wawrzek.name/CV/cv.pdf
    Link to this post 06 Nov 09

    I wrote bofh of my MSc and PhD theis in LaTeX (as well some scientific paper) and many presentation, however, it's not so popular among chemists.

    I also have my CV written in LaTeX. It's nice because gives special and fresh look and feel.

    http://wawrzek.name/CV/cv.pdf

  • Wawrzek
    RE: Sendfile and memory cache
    Thanks for great response. As each good response it lead to further question. Do data cached by kernel have to fit into 1GB of kernel memory? Is there different in handling this memory between 32bit and 64bit version of x86 arch? I'm asking because on a busy 32-bit server (apache serving static content - from 2 or 3 week non-stop) I see: [code] ~ > free total used free shared buffers cached Mem: 16633136 3370264 13262872 0 520812 2391332 -/+ buffers/cache: 458120 16175016 Swap: 1052248 88 1052160 [/code] My estimation is that if the system kept all served files in the cache the memory would filled in few hours. So there are some software limit of the memory usage.
    Link to this post 06 Nov 09

    Thanks for great response. As each good response it lead to further question.

    Do data cached by kernel have to fit into 1GB of kernel memory?

    Is there different in handling this memory between 32bit and 64bit version of x86 arch?

    I'm asking because on a busy 32-bit server (apache serving static content - from 2 or 3 week non-stop) I see:


    ~ > free
    total used free shared buffers cached
    Mem: 16633136 3370264 13262872 0 520812 2391332
    -/+ buffers/cache: 458120 16175016
    Swap: 1052248 88 1052160

    My estimation is that if the system kept all served files in the cache the memory would filled in few hours. So there are some software limit of the memory usage.

  • Wawrzek
    Sendfile and memory cache
    Could you please confirm or denied that system call sendfile(), opposite to read()+write() operations, does not use memory cache at all. What means that i.e. in an Apache serving many times the same static content turning [b]EnableSendfile Off[/b] might bust the performance, because files would be read from memory rather then from disk.
    Link to this post 05 Nov 09

    Could you please confirm or denied that system call sendfile(), opposite to read()+write() operations, does not use memory cache at all.

    What means that i.e. in an Apache serving many times the same static content turning EnableSendfile Off might bust the performance, because files would be read from memory rather then from disk.

  • Wawrzek
    RE: Linux & SSDs (Solid State Drives)
    Please check the link under the following article on my blog: http://larryn.blogspot.com/2009/08/stone-redskin-comparision-of-apache2.html BTW. In the article there are some test of Apache on HDD and SSD. Might be interested for some.
    Link to this post 05 Nov 09

    Please check the link under the following article on my blog:

    http://larryn.blogspot.com/2009/08/stone-redskin-comparision-of-apache2.html

    BTW. In the article there are some test of Apache on HDD and SSD. Might be interested for some.

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