Shinguz's blog

We see sometimes at customers that they have very big InnoDB system tablespace files (ibdata1) although they have set innodb_file_per_table = 1.

In the recent MariaDB DBA advanced training class the question came up if MariaDB can make use of an index when searching for NULL values… And to be honest I was not sure any more. So instead of reading boring documentation I did some little tests:

# free
              total        used        free      shared  buff/cache   available
Mem:       16106332     3914228      367072      296508    11825032    11441608
Swap:      31250428      182924    31067504

# cat /proc/meminfo | grep ^Swap
SwapCached:        10056 kB
SwapTotal:      31250428 kB
SwapFree:       31067504 kB

# for file in /proc/*/status ; do
  awk '/VmSwap|Name/{
    if ( $2 != "0" )
      printf $2 " " $3
  }END{ print ""}' $file
done | grep kB | sort -k 2 -n -r

mysqld 29988 kB
plasmashell 19096 kB
kwin_x11 13444 kB
Xorg 13328 kB
krunner 11200 kB
knotes 5768 kB
kded5 5016 kB
korgac 4760 kB
kglobalaccel5 3288 kB
kwalletd 3148 kB
kaccess 3148 kB
polkit-kde-auth 2704 kB
xembedsniproxy 2660 kB
akonadi_control 2652 kB
kwalletd5 2616 kB
python 2572 kB
kactivitymanage 2508 kB
klauncher 2352 kB
kdeinit5 2324 kB
ksmserver 2256 kB
python 1480 kB
pulseaudio 1312 kB
sddm-helper 1172 kB
baloo_file 1172 kB
kscreen_backend 1132 kB
mission-control 1104 kB
python 992 kB
TeamDrive.bin 772 kB
sddm 772 kB
akonadiserver 616 kB
systemd 504 kB
at-spi2-registr 488 kB
systemd 472 kB
kwrapper5 468 kB
dbus-launch 400 kB
dbus-launch 396 kB
(sd-pam) 364 kB
dbus-daemon 328 kB
(sd-pam) 300 kB
at-spi-bus-laun 264 kB
obexd 260 kB
ssh-agent 252 kB
dbus-daemon 216 kB
gnome-keyring-d 212 kB
dbus-daemon 200 kB
gpg-agent 104 kB
startkde 100 kB
skypeforlinux 64 kB
start_kdeinit 60 kB
apache2 32 kB
apache2 32 kB
apache2 32 kB
apache2 32 kB
apache2 32 kB
apache2 32 kB

# sudo smem --totals --sort=swap
  PID User     Command                         Swap      USS      PSS      RSS
...
 1500 root     /usr/sbin/apache2 -k start        32     5616     9534    23740 
10469 www-data /usr/sbin/apache2 -k start        32      136     1421     9848 
10470 www-data /usr/sbin/apache2 -k start        32      132     1418     9848 
10471 www-data /usr/sbin/apache2 -k start        32      132     1418     9848 
10472 www-data /usr/sbin/apache2 -k start        32      132     1418     9848 
10473 www-data /usr/sbin/apache2 -k start        32      132     1418     9848 
 2111 oli      /usr/lib/x86_64-linux-gnu/l       60       40       43      548 
 2291 oli      /usr/share/skypeforlinux/sk       60    73920    80765   106312 
 1957 oli      /bin/sh /usr/bin/startkde        100        8       54     1576 
 2050 oli      /usr/bin/gpg-agent --daemon      104      256      278     1924 
 2056 oli      /usr/bin/dbus-daemon --fork      200     1740     1820     4480 
 1951 oli      /usr/bin/gnome-keyring-daem      212      704      887     5768 
 2132 oli      /usr/bin/dbus-daemon --conf      216      712      806     3924 
 2052 oli      /usr/bin/ssh-agent /usr/bin      252      204      209      908 
 2315 oli      /usr/lib/bluetooth/obexd         260     1084     1345     7936 
 2127 oli      /usr/lib/at-spi2-core/at-sp      264      536      625     5700 
 1228 sddm     (sd-pam)                         300     1412     1728     3036 
 1476 sddm     /usr/bin/dbus-daemon --fork      328       56      143     2748 
 1946 oli      (sd-pam)                         364     1216     1615     3132 
 1475 sddm     dbus-launch --autolaunch 61      396        8       28     2252 
 2055 oli      /usr/bin/dbus-launch --exit      400        8       24     2160 
 1223 sddm     /lib/systemd/systemd --user      444      432      995     4376 
 1937 oli      /lib/systemd/systemd --user      448      404      971     4400 
 2144 oli      kwrapper5 /usr/bin/ksmserve      468        4      102     6356 
 2134 oli      /usr/lib/at-spi2-core/at-sp      488      268      343     5776 
 2223 oli      akonadiserver                    616    11196    11401    21988 
 1129 root     /usr/bin/sddm                    724      716      963    11848 
 2277 oli      ./TeamDrive.bin autostart        772   352656   353309   365768 
 2298 oli      python /usr/bin/hp-systray       992     4904     7157    15340 
 2162 oli      /usr/lib/telepathy/mission-     1104     1196     1540     8640 
 2166 oli      /usr/lib/x86_64-linux-gnu/l     1132      696      973    15148 
 1934 root     /usr/lib/x86_64-linux-gnu/s     1172      352      802    10996 
 2177 oli      /usr/bin/baloo_file             1172    74356    74784    90584 
 2208 oli      /usr/bin/pulseaudio --start     1312     4520     4897    10672 
 2299 oli      python /usr/bin/hp-systray      1480     3152     5448    11184 
 2146 oli      /usr/bin/ksmserver              2256     5024     6013    34104 
 2115 oli      kdeinit5: Running...            2324      264      748    15492 
 2116 oli      klauncher [kdeinit5] --fd=9     2352     1256     1997    21712 
 2154 oli      /usr/bin/kactivitymanagerd      2472     4588     5337    29772 
 2284 oli      python /usr/bin/hp-systray      2572    15216    18372    37452 
 1956 oli      /usr/bin/kwalletd5 --pam-lo     2616     5272     6454    37400 
 2219 oli      /usr/bin/akonadi_control        2652     2048     2450    23964 
 2195 oli      /usr/bin/xembedsniproxy         2660      968     1405    23600 
 2190 oli      /usr/lib/x86_64-linux-gnu/l     2704     1172     1703    26716 
 1954 oli      /usr/bin/kwalletd --pam-log     3144     1180     1601    12784 
 2124 oli      /usr/bin/kaccess                3148      708     1110    21276 
 2151 oli      /usr/bin/kglobalaccel5          3288     1316     1799    25164 
 2203 oli      /usr/bin/korgac -session 10     4760     1384     2093    28576 
 2118 oli      kded5 [kdeinit5]                5016    77440    78828   107932 
 2217 oli      /usr/bin/knotes -session 10     5768     7048     8467    41744 
 2179 oli      /usr/bin/krunner               11200    16276    19166    55272 
 1148 root     /usr/lib/xorg/Xorg -noliste    13316    31464    45953    68016 
 2167 oli      kwin_x11 -session 106368656    13444    35972    39318    76556 
 2186 oli      /usr/bin/plasmashell --shut    19096    90608    94701   135284 
 2224 oli      /usr/sbin/mysqld --defaults    29988   148588   148624   151832 
-------------------------------------------------------------------------------
  170 14                                     150808  4085792  4318525  6436312 

# sudo smem --totals --sort=swap | grep -e mysql -e Command
  PID User     Command                         Swap      USS      PSS      RSS 
 6903 mysql    /home/mysql/product/mariadb        0   191000   191071   194964 
16937 mysql    /home/mysql/product/mysql-8        0   358812   358865   362364 
17480 mysql    /home/mysql/product/mysql-5        0   271420   273310   278692 
28484 root     grep -e mysql -e Command           0      352      395     2404 
29071 mysql    /bin/sh bin/mysqld_safe --d        0      152      227     1724 
29326 mysql    /home/mysql/product/mysql-5        0   506848   508747   514268 
 2224 oli      /usr/sbin/mysqld --defaults    29988   148588   148624   151832 

A while ago we released our FromDual Backup and Recovery Manager (brman) 2.0.0 for MariaDB and MySQL. So what are the new cool features of this new release?

FromDual has the pleasure to announce the release of the new version 2.0.0 of its popular Backup and Recovery Manager for MariaDB and MySQL (brman).

MariaDB Bug number 16476: https://jira.mariadb.org/browse/MDEV-16476. Seems like it will be fixed soon…?

MariaDB 10.3 was released GA a few weeks ago. One of the features which interests me most is the MariaDB Oracle PL/SQL compatibility mode.

Due to a strong customer demand FromDual offers 2018 two extra MySQL/MariaDB trainings with its Training partner The Linuxhotel in Essen (Germany). Those trainings are in English.

Coming soon…

FromDual as a neutral and vendor independent database service company also provides various services for the MariaDB database.

MySQL has introduced the PERFORMANCE_SCHEMA (P_S) in MySQL 5.5 and made it really usable in MySQL 5.6 and added some enhancements in MySQL 5.7 and 8.0.

The Chemnitz Linux Days 2018 in Chemnitz (Germany) 10/11 March 2018 are over for more than a week now and IMHO it was a huge success.

Due to the increasing demand FromDual has developed an Advanced MySQL Enterprise Training for DBAs and DevOps. After testing this training extensively with some selected customers last year we offer this MySQL Enterprise Training in 2018 for a broader audience.

Yesterday MySQL 8.0.4-rc came out. The Release Notes are quite long.
But caution: Do a BACKUP before upgrading…

FromDual offers short term a Percona XtraDB Cluster and MySQL Galera Cluster training (2 days) in English.

End of February, from February 26 to March 2 (5 days), FromDual offers an additional training for DBAs and DevOps: our most visited Advanced MySQL and MariaDB training.

As in every quarter of the year Oracle has released yesterday its recommendation for the MySQL security updates. This is called, in Oracle terminology, Critical Patch Update (CPU) Advisory.

If you are already familiar with MySQL and you are challenged to operate a serious MySQL Enterprise infrastructure this training is the right one for you.

Today we had to investigate in a very strange behaviour of IST and SST on a MariaDB Galera Cluster.

The Docker version of the distributions are often quite old. On Ubuntu 16.04 for example: