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To: emz@norma.perm.ru, slw@zxy.spb.ru
Subject: Re: zfs, a directory that used to hold lot of files and listing pause
Cc: freebsd-stable@freebsd.org
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From: Pete French <petefrench@ingresso.co.uk>
Date: Fri, 21 Oct 2016 13:47:08 +0100
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> In bad case metadata of every file will be placed in random place of disk.
> ls need access to metadata of every file before start of output listing.

Umm, are we not talkong abut an issue where the directoyr no longer contains
any files. It used to have lots, now it has none.

> I.e. in bad case you will be need tens of thousands seeks over disk
> capable only 72 seeks per seconds.

Why does it need to seek all over the disc if there are no files (and hence
no metadata surely) ?

I am not bothered if a hufge directoyr takes a while to list,
thats something I am happy to deal with. What I dont like is
when it is back down to zero that it still takes a long time
to list. That doesnt make much sense.

-pete.