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<p class="MsoNormal"><span lang="EN-US">Hi!<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">In SLES15 SP6 (systemd-254.24-150600.4.28.1.x86_64) I noticed that collecting logs took quite long, so I checked.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"># time journalctl |wc -l<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">2705448<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">real 2m23.008s<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">user 1m25.666s<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">sys 0m57.389s<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The journal is persistent and it’s located on a BtrFS subvolume using a device that is provided by VMware from a high-performance SSD SAN storage:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"># lsblk<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINTS<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">sda 8:0 0 40G 0 disk<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Arial",sans-serif">†</span><span lang="EN-US">€</span><span lang="EN-US">sda1 8:1 0 512M 0 part /boot/efi<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Arial",sans-serif">†</span><span lang="EN-US">€</span><span lang="EN-US">sda2 8:2 0 21G 0 part /root<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> /srv<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> /usr/local<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> /var<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> /opt<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> /tmp<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> /boot/grub2/x86_64-efi<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> /boot/grub2/i386-pc<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> /.snapshots<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> /<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:"Arial",sans-serif">†</span><span lang="EN-US">€</span><span lang="EN-US">sda3 8:3 0 10.7G 0 part /home<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">„€sda4 8:4 0 7.8G 0 part [SWAP]<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"># hdparm -t /dev/sda2<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">/dev/sda2:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Timing buffered disk reads: 1680 MB in 3.00 seconds = 559.48 MB/sec<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"># hdparm -T /dev/sda2<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">/dev/sda2:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Timing cached reads: 18612 MB in 2.00 seconds = 9322.49 MB/sec<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">During boot this statistics had been logged:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">System Journal (/var/log/journal/41d6ce7a6cfc467297b777b8d87f071d) is 2.0G, max 2.1G, 103.1M free.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Obvious question: Why is it so slow?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Kind regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Ulrich Windl<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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