From mboxrd@z Thu Jan  1 00:00:00 1970
From: Spelic <spelic@shiftmail.org>
Subject: Re: du -s src is a lot slower on SSD than spinning disk in the same
 laptop
Date: Wed, 01 Aug 2012 10:18:56 +0200
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References: <20120725154521.GA3398@merlins.org>
 <20120726033223.GA5884@thunk.org> <20120726065412.GB20315@merlins.org>
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On 08/01/12 07:30, Marc MERLIN wrote:
> 2) Then I put a crucial 256 C300 SSD (the replacement for the one I 
> had that just died and killed all my data), and du took 0.3 seconds on 
> both my old and new thinkpads. 


What does FIO say on your Samsung 830 SSD, 4k random reads?
Last time I checked online benchmarks Samsung 830 had very good 4k 
random reads, but it's difficult to find online benchmarks for 
incompressible data (which fio rightly uses btw)

multithreded test:
vi fiotest_mt.fio
         [random-read]
         rw=randread
         numjobs=20
         thread
         iodepth=10
         group_reporting
         blocksize=4k
         size=512m
         directory=/mnt/<yourmountpoint>
         end_fsync=1
         runtime=10

and single threaded (more important here):
vi fiotest_st.fio
         [random-read]
         rw=randread
         numjobs=1
         thread
         iodepth=1
         group_reporting
         blocksize=4k
         size=4g
         directory=/mnt/<yourmountpoint>
         end_fsync=1
         runtime=10