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STATUS updates
Some links of interest:
Aside from an attempt at restarting my status-reporting habits in January of 2017, I totally neglected it for the remainder of the year.
So here we go, attempting another go. Will we be successful?
In other recent projects, I encountered some useful configuration options to improve performance, and avoid some anti-longevity side-effects of default settings.
I ended up taking a Debian USB installer, booting each pod in rescue mode, getting to a prompt, and running the following on EACH:
# umount / # tune2fs -O ^has_journal /dev/sda1 # tune2fs -o discard /dev/sda1
Then on the master nodes, I enhanced both /etc/fstab and /etc/rc.local as follows:
# /etc/fstab: static file system information. # # <file system> <mount point> <type> <options> <dump> <pass> /dev/sda1 / ext4 noatime,nodiratime,discard,commit=600,errors=remount-ro 0 1 tmpfs /tmp tmpfs defaults,noatime,mode=1777 0 0 tmpfs /var/log tmpfs defaults,noatime,mode=1777 0 0 tmpfs /var/spool tmpfs defaults,noatime,mode=1777 0 0 tmpfs /var/tmp tmpfs defaults,noatime,mode=1777 0 0
Note how I put the log files in RAM too (on the pods)… this should greatly reduce extraneous writes.
Then at the bottom of /etc/rc.local, I added:
#!/bin/sh -e # # rc.local # IPADDR= while [ -z "${IPADDR}" ]; do IPADDR=`/usr/local/bin/iface | /bin/grep -v 'lo' | /usr/bin/head | /usr/bin/cut -d' ' -f2` sleep 1 done /bin/hostname `/usr/bin/host ${IPADDR} | /usr/bin/cut -d' ' -f5 | /bin/sed s/\.$//` /usr/bin/host ${IPADDR} | /usr/bin/cut -d' ' -f5 | /bin/sed s/\.$// > /etc/hostname echo "${IPADDR} `cat /etc/hostname`" > /etc/hosts echo "127.0.0.1 localhost" >> /etc/hosts echo "10.80.2.46 lab46.g7n.org lab46.corning-cc.edu" >> /etc/hosts echo deadline > /sys/block/sda/queue/scheduler echo 1 > /sys/block/sda/queue/iosched/fifo_batch exit 0
As the deadline scheduler has frequent mention of usage with SSDs.
Useful URLs:
With the pods having seen their SSD updates, I am looking to do the same for lab46too, testing to make sure the similar changes can be applied to that machine before rolling them over to lab46 proper.
I've updated the /etc/fstab and /etc/rc.local files accordingly on lab46, so those changes have been synced over to lab46too on a recent rsync run.