SMART criteria

SMART is a mnemonic acronym, giving criteria to guide in the setting of objectives, for example in project management, employee-performance management and personal development. The letters S and M usually mean specific and measurable. The other letters have meant different things to different authors, as described below. Additional letters have been added by some authors. SMART criteria are commonly associated with Peter Drucker’s management by objectives concept.[1] The first-known use of the term occurs i

Source: SMART criteria – Wikipedia

SMART criteria was last modified: September 25th, 2017 by Jovan Stosic

MySQL Replication: ‘Got fatal error 1236’ causes and cures

MySQL Replication: ‘Got fatal error 1236’ causes and cures

MySQL Replication: 'Got fatal error 1236' causes and curesMySQL replication is a core process for maintaining multiple copies of data – and replication is a very important aspect in database administration. In order to synchronize data between master and slaves you need to make sure that data transfers smoothly, and to do so you need to act promptly regarding replication errors to continue data synchronization. Here on the Percona Support team, we often help customers with replication broken-related issues. In this post I’ll highlight the top most critical replication error code 1236 along with the causes and cure. MySQL replication error “Got fatal error 1236” can be triggered by multiple reasons and I will try to cover all of them.

Source: MySQL Replication: ‘Got fatal error 1236’ causes and cures

MySQL Replication: ‘Got fatal error 1236’ causes and cures was last modified: July 13th, 2017 by Jovan Stosic

The Mystery of the Vanishing Disk Space – Ask Ubuntu

My disk space is dwindling by about 2GB a day! I only have a few more days before I run out of space.

$ df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda4             143G  126G   11G  93% /
udev                  491M  4.0K  491M   1% /dev
tmpfs                 200M  696K  199M   1% /run
none                  5.0M     0  5.0M   0% /run/lock
none                  499M  144K  499M   1% /run/shm
/dev/sda2             1.9G  580M  1.2G  33% /tmp
/dev/sda1              92M   29M   58M  33% /boot

I have been searching for the biggest directories/log files, deleting and compressing. But I am still losing the war. Finally, I realised I have a big misunderstanding:

julian@server1:~$ sudo du -h / | tail -n 1
16G     /

All of my files in / only add up to 16 GB. That leaves 110 GB unaccounted for!

Clearly I have a misunderstanding: I thought the ‘/dev/sda4’ line represented all the files visible from ‘/’. What should I be reading to understand where the other storage has gone?

More details:

  • I have an Ubuntu 11.10 server, that was set-up by data-center staff.
  • It is running
    • my own code (which is fairly prolific with log files, but otherwise doesn’t store much stuff on the drive)
    • duplicity for backups (which tends to store a lot of signature files)
    • various other standard services, like Apache, nagios, etc. They are very lightly used.
  • It has been up for about 4 months without a reboot.
  • I lied about the du output (simplified it for effect). It also complained about not being able to access GVFS and the du processes’s own resources. I believe they are irrelevant:

.

 du: cannot access `/home/julian/.gvfs': Permission denied
 du: cannot access `/proc/10841/task/10841/fd/4': No such file or directory
 du: cannot access `/proc/10841/task/10841/fdinfo/4': No such file or directory
 du: cannot access `/proc/10841/fd/4': No such file or directory
 du: cannot access `/proc/10841/fdinfo/4': No such file or directory

Source: The Mystery of the Vanishing Disk Space – Ask Ubuntu

The Mystery of the Vanishing Disk Space – Ask Ubuntu was last modified: July 13th, 2017 by Jovan Stosic