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From: John Lindgren <john.lindgren@tds.net>
To: util-linux@vger.kernel.org
Subject: blkid: excessive random reads probing for ZFS on NTFS filesystem
Date: Sun, 12 Jun 2011 15:02:48 -0400	[thread overview]
Message-ID: <4DF50D58.9020800@tds.net> (raw)

Hi,

I noticed blkid causing a noticeable amount of disk hits while
identifying an NTFS (Win7) partition, and did an strace to find out why
this was.  It seems that the probe_zfs() function does a
seek-and-read-41-bytes pattern 64 times in the 130 to 520 KB region of
the partition.  This of course is slow on a traditional hard disk, and
seems excessive.  I don't know the internals of NTFS or of ZFS.  Can
someone with a little more knowledge in this area provide some pointers
as to why this might be happening?

-- John Lindgren

             reply	other threads:[~2011-06-12 19:03 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-06-12 19:02 John Lindgren [this message]
2011-06-20 11:16 ` blkid: excessive random reads probing for ZFS on NTFS filesystem Karel Zak
2011-06-20 11:59   ` John Lindgren
2011-06-20 12:46     ` Karel Zak
2011-06-20 13:05       ` John Lindgren
2011-06-20 14:04         ` Karel Zak
2011-06-20 14:20           ` John Lindgren
2011-06-20 14:57             ` Karel Zak
2011-06-20 12:02   ` John Lindgren

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