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From: "Valdis Klētnieks" <valdis.kletnieks@vt.edu>
To: Mulyadi Santosa <mulyadi.santosa@gmail.com>
Cc: kernelnewbies <Kernelnewbies@kernelnewbies.org>
Subject: Re: Is there some method or software that could purposely generate a lot of physical memory fragmentations on linux?
Date: Fri, 03 Jul 2020 00:58:37 -0400
Message-ID: <6499.1593752317@turing-police> (raw)
In-Reply-To: <CAGdaadbZES2x-JWdA3xFwk8wuu=bULd3X3775Se43ZSkWzFFLw@mail.gmail.com>

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On Thu, 02 Jul 2020 15:29:18 +0700, Mulyadi Santosa said:

> Just pseudo idea, if this is in user space, try to:  allocate many blocks
> of memory using malloc, each having different size, keep the returned
> pointer, then randomly free() some of them, then malloc() again with
> different size

That will cause userspace malloc() to have fragmentation, but as far
as the kernel is concerned it's all just 4K pages of user memory.

Causing physical memory fragmentation will require abusing the kernel
memory allocators such as kmalloc() and vmalloc() and friends.

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Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-30  6:51 孙世龙 sunshilong
2020-07-02  8:29 ` Mulyadi Santosa
2020-07-03  4:58   ` Valdis Klētnieks [this message]
2020-07-03  5:20 ` 孙世龙 sunshilong

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