MySQL Bugs: #67252: Very slow fetching of even small query results with MySQL 5.6.7

Bug #67252	Very slow fetching of even small query results with MySQL 5.6.7
Submitted:	16 Oct 2012 7:16	Modified:	17 Oct 2013 6:07
Reporter:	Olag Ulga	Email Updates:
Status:	Duplicate	Impact on me:	None
Category:	MySQL Workbench: SQL Editor	Severity:	S3 (Non-critical)
Version:	5.2.43 5.2.44, 5.2.45, 5.2.47	OS:	Microsoft Windows (Win8x64 Win7x64)
Assigned to:		CPU Architecture:	Any
Tags:	slow fetching result
Triage:	Needs Triage: D2 (Serious)

Description:
Fetching of a query result in SQL Editor is very slow with MySQL 5.6.7-rc-log, Win64. With other sql tools the problem does not occure.

How to repeat:
- Start Workbench and open the sql editor with a connection to MySQL 5.6.7-rc-log
- Open new query tab (CTRL + T)
- Execute:
CREATE SCHEMA `slow`;
Use `slow`;
CREATE  TABLE `tblSlow` (
  `Id` INT NOT NULL AUTO_INCREMENT ,
  PRIMARY KEY (`Id`) )
ENGINE = InnoDB;
- Refresh the object browser that it displays the slow schema
- go to the tblslow and click 'Select Rows - Limit 1000' in the context menu
- now it takes several seconds to fetch the empty result despite the execution duration from the output panel displays 0.000 seconds

Suggested fix:
the result should be displayed instantly

Thank you for the bug report. I can't to repeat on 2 different machines running Windows 7 64-bit (Ultimate/Professional). Your connection is local or remote? Against which MySQL server version are you queyring?. Thanks.

The Server is MySQL 5.6.7-rc-log, Win64 running on Win 7 x64 / Enterprise.

The problem is reproducible if Workbench is running on the same machine over TCP/IP to localhost or from another machine in the LAN over TCP/IP running on Win 8 x64 / Enterprise.

I tested some more things and it seems that it is fast with one database and becomes slow with more databases (tested with 71 databases). The original problem server has 427 databases. With MySQL 5.5 and 5.1 this is no problem.

Thank you for the feedback. Then the main point to be repeatable is to have around 71 databases in the server?. Thanks.

Yes the problem occures if you have a lot of databases.

Could you please verify this bug. It is annoying!

Thanks

Thank you for the feedback.

Still not fixed in 5.2.47

It's the same on 5.2.47 for OSX (mountain Lion).
With 10 database with about 100 tables each one, I got about 6 or 7 seconds for getting tables content. After deleting 8, now it's just 1 or 2 seconds...

I forgot. I'm using mysql 5.6, and I'm on a mac pro 6-core with 12GB RAM.
MySQL is fast with PHP or using SequelPro.
It's slow just with Workbench.
All my databases are local.

Duplicate of bug #55364

same issue for me. fetching 1 row in one table, and one database. Yet it takes ~30sec to fetch the data. Duration log shows 0.050 sec for duration and 0.000 sec for fetching.

The Bug #55364 describes a completely different behaviour. It describes a performance problem, if selecting large amount of data. This bug describes a performance problem, if selecting very few data. 

changelog entry of #55364: "MySQL Workbench suffered from slow performance when selecting a large amount of data, such as 100,000+ rows."

I don't think that this bug is a dupplicate of #55364.

@Alfredo Kengi Kojima: Why should this be a dupplicate???

I will try to reproduce with MySQL Workbench 6.0.3 in 3 weeks.

Fixed in 6.0.7