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From: kazushi takahashi <w1ndoz@triton.ocn.ne.jp>
To: qemu-devel@nongnu.org
Subject: [Qemu-devel] Question about IDE TRIM Command
Date: Thu, 2 Feb 2012 22:20:40 +0900	[thread overview]
Message-ID: <CAMQKM2_qL_d1Ltmk5rerc4jFB59kAZrsswhiWJL=bcOCAoeyDA@mail.gmail.com> (raw)

Hi all

I have a question about IDE TRIM Command.

As you know, QEMU have supported TRIM command since QEMU 0.15.0.

Some QEMU disk images such as qcow2 support bdrv_discard function
which will be called when guest OS executes ATA TRIM command.

So, I think qcow2 image has a function to delete the disk pages which are
recognized as discarded by guest OS.

I think that to enable TRIM Command, we have to emulate guest HDD as
Solid State Drive. However, it seems QEMU does not emulate guest
HDD as Solid State Drive. Thus, I think that bdrv_discard functions in
qemu images are never called by guest OS.

Is my thinking correct?

Thanks,
Kazushi Takahashi

             reply	other threads:[~2012-02-02 13:20 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-02-02 13:20 kazushi takahashi [this message]
  -- strict thread matches above, loose matches on Subject: below --
2012-02-02 11:55 [Qemu-devel] Question about IDE TRIM Command kazushi takahashi

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