diff options
Diffstat (limited to 'issues/systems/mariadb/ProbeSetData.gmi')
-rw-r--r-- | issues/systems/mariadb/ProbeSetData.gmi | 83 |
1 files changed, 76 insertions, 7 deletions
diff --git a/issues/systems/mariadb/ProbeSetData.gmi b/issues/systems/mariadb/ProbeSetData.gmi index 91179c3..9fceea9 100644 --- a/issues/systems/mariadb/ProbeSetData.gmi +++ b/issues/systems/mariadb/ProbeSetData.gmi @@ -14,15 +14,16 @@ This is by far the largest table (~200Gb). I need to add disk space to be able t This time I failed porting to InnoDB (see Migration below): -* [ ] Move database to larger drive -* [ ] Run second instance of mariadb using a Guix container, upgrade too? -* [ ] Stop binary log -* [ ] Drop the indices -* [ ] Try different sizes of innodb exports +* [X] Move database to larger drive (stop Mariadb for final stage) +* [X] Stop binary log (SET sql_log_bin = 0;) +* [X] Run second instance of mariadb using a Guix container, upgrade too? +* [X] Drop the indices +* [X] Try different sizes of innodb exports * [ ] Make (ordered) conversion and test performance * [ ] Rebuild indices -* [ ] Restart binary log +* [ ] Test performance * [ ] Muck out ibdata1 and transaction logs +* [ ] Restart binary log (SET sql_log_bin = 1;) I disabled these and they need to be restored: @@ -302,7 +303,75 @@ next copy the database to a new partition: root@tux01:/export4/local/home/mariadb/database/db_webqtl# rsync -vaP /var/lib/mysql/db_webqtl/* . --delete --bwlimit=20M ``` -Note I throttle the speed because the system can become quite unusable at full copy speed. +Note I throttle the speed because the system can become quite unusable at full copy speed. Next I stopped Mariadb and made sure the copy is completed. After restarding mariadb I could continue work on the copy using a guix shell instance as described in + +=> setting-up-local-development-database.gmi + +Steps were as a normal user + +``` +tux01:/export4/local/home/mariadb$ ~/opt/guix-pull/bin/guix pull -p ~/opt/guix-latest +. ~/opt/guix-latest/etc/profile +mkdir var +guix shell -C -N coreutils sed mariadb --share=var=/var +mysqld_safe --datadir='./database' --user=$USER --nowatch --socket=/var/run/mysqld/mysqld.sock +mysql --socket=/var/run/mysqld/mysqld.sock -uwebqtlout -p db_webqtl +``` + +OK, now it is running and we can start experimenting with the table outside the main database setup. Remember we had + +``` +ProbeSetData | CREATE TABLE 'ProbeSetData' ( + 'Id' int(10) unsigned NOT NULL DEFAULT 0, + 'StrainId' int(20) NOT NULL, + 'value' float NOT NULL, + UNIQUE KEY 'DataId' ('Id','StrainId'), + KEY 'strainid' ('StrainId') +) ENGINE=MyISAM DEFAULT CHARSET=latin1 +``` + +``` +DROP INDEX strainid ON ProbeSetData; +DROP INDEX DataId ON ProbeSetData; +``` + +of course it starts making a copy of the whole table and takes hours(!) This is why we need over 200Gb free both on the DB directory and the tempdir of the mariadb server. + +``` +select count(Id) from ProbeSetData; ++------------+ +| count(Id) | ++------------+ +| 5173425135 | ++------------+ +MariaDB [db_webqtl]> select max(Id),max(StrainId) from ProbeSetData; ++----------+---------------+ +| max(Id) | max(StrainId) | ++----------+---------------+ +| 92199993 | 71224 | ++----------+---------------+ +MariaDB [db_webqtl]> select * from ProbeSetData limit 4; ++----+----------+-------+ +| Id | StrainId | value | ++----+----------+-------+ +| 1 | 1 | 5.742 | +| 1 | 2 | 5.006 | +| 1 | 3 | 6.079 | +| 1 | 4 | 6.414 | ++----+----------+-------+ +``` + +``` +ALTER TABLE ProbeSetData MODIFY StrainId mediumint UNSIGNED NOT NULL; +``` + +Now the table is 58Gb without indices. Convert to innodb and add indices + +``` +CREATE INDEX id_index ON ProbeSetData(Id); +ALTER TABLE ProbeSetData ENGINE = InnoDB; +``` + ## Notes |