InnoDB : MySQL's ACID-compliant Storage Engine

learn more… | top users | synonyms

5
votes
1answer
252 views

“Site Offline” MySQL server failing to start and stop

I'm hosting a few sites on linode and have encountered a strange problem. For the last two years the site has been running perfectly fine, and now randomly all the websites on the server go to the ...
4
votes
2answers
3k views

Internal reason for killing process taking up long time in mysql

I copied a big table's structure with (it is an InnoDB table btw) CREATE TABLE tempTbl LIKE realTbl Then I changed an index, and filled it up so I could run some test. Filling it was done using: ...
3
votes
1answer
690 views

Can I reset the ibdata1 and ib_logfile files when innodb_file_per_table is already in place

I am running into an issue where sensitive data was not encrypted properly at the application level of our production system. Even though the guilty records have been removed or corrected, scanning ...
3
votes
5answers
2k views

TokuDB not much faster than MySQL

I have converted a MySQL database with 80.000.000 rows to TokuDB. Now when I run: select count(id) from xxx where active=1 it takes 90% of the time of the normal MySQL request. What do I have to ...
3
votes
2answers
465 views

Database space doesn't match ibdata1 size

I'm using InnoDB database with a single file configuration (in /var), so no innodb_file_per_table. In the MySql workbench, when I query for the databases used space, with this query SELECT ...
3
votes
1answer
2k views

error 1118: row size too large. utf8 innodb

I have tried to find a solution guys, and I am guessing that someone has met this before. But I cannot get hits down below 5000... most of which don't match my question. Using MySQL 5.6 - windows ...
3
votes
1answer
3k views

Move ibdata1, set innodb_data_file_path

I am in a bit of an awkward situation right now. I have a database with a few large InnoDB tables, one of which is about 145 GiB. I have been running a lot of maintenance on this table in particular, ...
3
votes
1answer
405 views

MySQL - Installing InnoDB Plugin

I have a Master/Slave Replication Setup, both servers run MySQL 5.1.61. I want to upgrade the master server to a stronger machine with the following: 2 processors - 6 cores each 48GB of RAM To ...
3
votes
1answer
2k views

When are InnoDB table index statistics updated?

In a vanilla build of MySQL 5.5.20, when are InnoDB table index statistics updated? What events trigger such updates? I've seen comments suggesting that the following might trigger it: table is ...
3
votes
2answers
975 views

MySql replication with Raw Data and InnoDB tables

I want to start replication on DB that has many InnoDB tables and MyISAM tables. I did everything according to manual Creating a Data Snapshot Using Raw Data Files. Firstly, I tried copied all ...
3
votes
2answers
3k views

Using MySQL triggers or transactions?

I want to ask your opinion in using MySQL triggers or transactions in a website. Actually I have a history payment table with - UserId | OperationId | Comment | Credits | Sign (debit or credit). So ...
2
votes
1answer
60 views

row locking within ACID transaction innodb

I have a financial transaction that looks something like this (pseudo): begin select record for update update record(same record as selected) insert another record into another table ...
2
votes
1answer
122 views

How big can innodb_doublewrite_file grow?

When I use the enable innodb_doublewrite_file ... How big can this file grow ? How can I calculate the optimal disk size, if it would be used only for this file?
2
votes
1answer
3k views

How can extract the table schema from just the .frm file?

I have extracted the data directory of mysql from a backup and need to get the schema from an old table, however it's a backup from a different machine. I have read a fair number of tutorials today ...
2
votes
2answers
135 views

Are there implicit indexes in InnoDB like MyISAM?

If you have (id, a, b, c, d) table with primary key (id) and another key (a, b, c), in MyISAM that means that you also have the following implicit keys: (a) (a, b) (a, b, c, id) Is this valid for ...
2
votes
1answer
518 views

How does mysql deal with queries that touches myisam and innodb tables?

In our mysql database, we use both myisam and innodb tables, though there are more myisam tables. QUESTIONS If a query involves both myisam and innodb tables, will the query use table lock or row ...
2
votes
1answer
5k views

Mysql slowly uses memory until it starts to use swap

I am running a 1gb of RAM rackspace database server. For some reason in about 2 days the memory usage goes from using very little swap, to using 100mb. If I don't restart sql it will keep using more ...
2
votes
1answer
381 views

Database Design - Creating Multiple databases to avoid the headache of limit on table size

I need to design database to store information contained in millions of log files generated by devices on trial on network. My first approach was storing all the information in tables contained in a ...
2
votes
3answers
882 views

whether a big (but not used) ibdata1 slow anything down

Hi I have an ibdata1 that is around 10 gig. I have gradually migrated to 'file per table' using the innodb_file_per_table=1 option such that there are no big tables in ibdata1 anymore. I recently ...
2
votes
1answer
842 views

Transaction Lock Timeouts When Updating a Row

I'm trying to determine the cause of an InnoDB transaction lock timeout. This one is very strange in that it appears to be a deadlock error instead - nonetheless, here's the output of my slow log ...
2
votes
2answers
643 views

Is there any performance difference among MariaDB (xtradb plugin) and XtraDB Server for InnoDB?

Title says it all. However i have to enter at least 30 characters.
1
vote
2answers
400 views

How long can Deadlock info hold in innodb status page?

When I run SHOW ENGINE INNODB STATUS\G, I can see this timestamp ------------------------ LATEST DETECTED DEADLOCK ------------------------ 121118 17:14:31 Questions Any idea how long Deadlock ...
1
vote
1answer
659 views

How does innodb_stats_on_metadata relate to query execution plan stability?

The MySQL documentation for innodb_stats_on_metadata says "It can also improve the stability of execution plans for queries that involve InnoDB tables." That is a little vague. What is an example ...
0
votes
0answers
409 views

InnoDB errors after having deleted “ibdata1”

By accident, I have deleted the ibdata1 file in the MySQL directory because MySQL wasn't functioning correctly. After reading so many forums, I found a post that recommended deleting the 3 files ...
12
votes
2answers
3k views

Rows missing after online conversion from MyISAM to InnoDB

We have a reasonably small database that we wanted to convert from MyISAM to InnoDB. Being database noobs, we just converted (using alter table) without even taking the site down. Now that the ...
12
votes
5answers
11k views

Why do MySQL threads often show “freeing items” status when the query cache is disabled?

When I run SHOW PROCESSLIST, there are often a large number of INSERT/UPDATE threads in the "freeing items" state. The MySQL manual suggests that at least part of the reason for a thread to be in ...
6
votes
3answers
7k views

mysql wont start after increasing innodb_buffer_pool_size and innodb_log_file_size

I am following this solution here http://stackoverflow.com/questions/3927690/howto-clean-a-mysql-innodb-storage-engine/4056261#comment14041132_4056261 and tried to increase my innodb_buffer_pool_size ...
5
votes
5answers
5k views

MySQL said “InnoDB: Initializing buffer pool, size = 128.0M”, does it mean it is using 128MB RAM?

I am just using a very few InnoDB tables (e.g. less than 1MB), but during MySQL startup, it said InnoDB: Initializing buffer pool, size = 128.0M Does it mean even I am using in such a small size, ...
4
votes
1answer
1k views

Can SHOW TABLE STATUS query performance on MySQL be improved - Amazon RDS

I have a fairly large database on the Amazon Relational Database Service (RDS) running on MySQL 5.1.57. There are 900+ tables, so that running the "SHOW TABLE STATUS" query can take up to 30 seconds. ...
9
votes
1answer
10k views

Mysql Innodb: InnoDB: ERROR: the age of the last checkpoint is InnoDB: which exceeds the log group capacity

I really need some mysql expertize. I am a newbi to mysql and I am seeing some server crash of my db in the past 1 week. I am using mysql 5.1.36 on Ubuntu. This is a dedicated mysql server with Dual ...
4
votes
2answers
4k views

MySql - changing innodb_file_per_table for a live db

I have a large MySql DB (150GB) and only now i've noticed that the innodb_file_per_table is set to off which cause the entire DB to be hosted on one single file (ibdata1). i want to active ...
1
vote
5answers
7k views

Mysql: Insert performance INNODB vs MYISAM

I am inserting into a simple small table with 5 attributes and 1000 rows. I observed when the engine is INNODB, each insert is taking 0.03 - 0.05 seconds. I changed the engine to MYISAM, then the ...
7
votes
2answers
10k views

MySQL 5.1 InnoDB Configuration / 24GB RAM - bi-xeon high load

i'm running a facebook app which currently has 300 - 600 concurrent users (and growing). To get the hardware ready for growing i changed my i7 / 12gb ram / 2x 80gb intel x25 ssd's (debian 5.0 / mysql ...
4
votes
2answers
4k views

Percona vs MySQL

What is Percona? How does it differ from MySQL? When should we consider switching (or upgrading) from stock MySQL to Percona? To add some specifics in our situation we almost exclusively use ...
4
votes
2answers
584 views

Preordering the table by a specified column

I have a table and I am always getting the data by ordering a column. In my case, I order by datenum. However, the selection is so slow because of the ordering. Is it possible to order the table ...
2
votes
3answers
2k views

Is it normal to use many Triggers?

I have many so-called summary columns throughout my database to count number of rows in other tables. For example, counting the number of comments by a user (a column in the user table). Currently, I ...
0
votes
2answers
63 views

What variable(s) to look to maintain MySQL speed of scanning through all database tables while it starts?

We have few thousand small databases with total .ibd files of about 800000. We noticed that MySQL takes couple of minutes to stop but about two hours to start. For e.g. while MySQL is starting and ...
7
votes
2answers
749 views

Investigate peak in MySQL throughput

Recently one of our servers has ran out of memory and crashed. After reviewing the munin graphs, it appears that the only metric (other than memory usage) that peaked just before the crash was the ...
6
votes
2answers
13k views

How do I shrink the innodb file ibdata1 without dumping all databases?

InnoDB stores all tables in one big file ibdata1. After dropping a big table, the file is keeping its size no matter how big the table was. How can I shrink that file without having to dump and ...
5
votes
1answer
373 views

Possibilities to speed up InnoDB INSERTs and UPDATEs

My website retains user sessions in an innodb table. This usually works well, but a few hundred times a day, the INSERT and particularly the UPDATE statements run slower. I'm monitoring when, and it ...
5
votes
1answer
2k views

Find out MySQL index size for a concrete index

In MySQL, for InnoDB engine, how do I find out the size of one of the indexes I have in the same table ? I know I can select the index_length from information_schema.tables, but this gives the total ...
4
votes
2answers
236 views

Using MyISAM for reading and InnoDB for writing data

I read many articles about comparisons of MyISAM and InnoDB from performance point of view and I decided to use MyISAM for reading data and InnoDB for writing data. I want to use two structure like ...
4
votes
3answers
3k views

Mysql backup strategies?

We have a innodb mysql database so we are lost with lots of different mysql backup strategies. Some talk about mysqldump some talk about third part tools. Some of the tables we also plan to run ...
4
votes
3answers
572 views

Is Oracle DB immune to the InnoDB deadlocks found in MySQL?

It seems odd to me that MySQL would not handle this internally: "Deadlock found when trying to get lock; try restarting transaction" Does Oracle DB work around this issue? After all, Oracle owns ...
3
votes
2answers
443 views

How to split a string to and get info from another table in mysql

I have a system to assign score for each sentence stored in a column: TABLE 1: word_scores word score this 3 is 4 a 5 test 1 another 0 sentence 8 TABLE 2: ...
3
votes
1answer
2k views

Is Percona xtrabackup the right choice for my 500GB MySQL backup?

I have a MySQL db with 500GB, consisting mainly of Innodb tables, and one big (200GB) MyISAM table. My current backup strategy is copying the db files to an external harddrive. This causes a downtime ...
3
votes
1answer
594 views

InnoDB “corruption”

I use: 5.1.63-0ubuntu0.11.10.1 Apache/2.2.20 (Ubuntu) MySQL client version: 5.1.63 The system is continuously displaying the following error during reading data from a MySQL database: ...
3
votes
2answers
626 views

Should I move to InnoDB during a planned migration?

I'm shortly migrating a Debian Lenny webserver to another host and Debian Squeeze. The standard MySQL installation even on Squeeze is 5.1 and therefore would default to MyISAM - I'm inclined to stick ...
2
votes
1answer
81 views

AWS RDS showing large growth in Write Ops/sec, despite low # DB connections?

I have a Multi-AZ AWS RDS instance running MYSQL 5.5 I've noticed that my write ops/sec are growing fairly rapidly, despite low (and sometimes zero) DB connections - see charts for Avg write ops/sec ...
2
votes
2answers
2k views

MySQL 5.5 High CPU Usage

I have been working with a client with high traffic website(500k visitors and 600-800 active users at any given time). This uses wordpress and the DB is using MyISAM engine. The problem we had was ...