Re: MySQL 5.5.33 History list not purging?

[Brad Heller]

So I've done some more digging on this.


   1. Upgraded to MySQL 5.5.37
   2. Made sure we didn't have any old/long running transactions--nothing
   more than a few seconds.
   3. Did a dump/reload in to a new DB and started with an empty history
   list. A few days later, we're back up over 3mil in the list.

We're currently writing about 50MB/s to that machine. Is it possible the
purge thread just...can't keep up for some reason? How can I get better
visibility in to how quickly the purge thread is working vs. how many undo
entries are being put in the thread?

Thanks,


*Brad Heller *| Director of Engineering | Cloudability.com | 541-231-1514 |
Skype: brad.heller | @bradhe  | @cloudability


We're hiring! https://cloudability.com/jobs



On Sun, Sep 7, 2014 at 2:04 AM, Jesper Wisborg Krogh 
wrote:

> Hi Brad,
>
> > -Original Message-
> > From: Brad Heller [mailto:b...@cloudability.com]
> > Sent: Sunday, 7 September 2014 03:07
> > To: MySQL General List
> > Subject: MySQL 5.5.33 History list not purging?
> >
> > For some reason, the history list isn't purging on one of my masters.
> This is
> > causing all kinds of weird issues/behavior with reads. Here's the last 8
> or so
> > hours of history list length:
> >
> > http://i.imgur.com/Q4DEeVi.png
> >
>
> I would start looking for an old transaction. You can use SHOW ENGINE
> INNODB STATUS or the information_schema.INNODB_TRX table to look for that.
>
> Best regards,
> Jesper Krogh
> MySQL Support
>
>
>
> --
> MySQL General Mailing List
> For list archives: http://lists.mysql.com/mysql
> To unsubscribe:http://lists.mysql.com/mysql
>
>

RE: MySQL 5.5.33 History list not purging?

[Jesper Wisborg Krogh]

Hi Brad,

> -Original Message-
> From: Brad Heller [mailto:b...@cloudability.com]
> Sent: Sunday, 7 September 2014 03:07
> To: MySQL General List
> Subject: MySQL 5.5.33 History list not purging?
> 
> For some reason, the history list isn't purging on one of my masters. This is
> causing all kinds of weird issues/behavior with reads. Here's the last 8 or so
> hours of history list length:
> 
> http://i.imgur.com/Q4DEeVi.png
> 

I would start looking for an old transaction. You can use SHOW ENGINE INNODB 
STATUS or the information_schema.INNODB_TRX table to look for that.

Best regards,
Jesper Krogh
MySQL Support



--
MySQL General Mailing List
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Re: MySQL 5.5.33 History list not purging?

[Brad Heller]

Good point. We'll try that out.

I noticed our ibdata file is gigantic now, likely due to the alter table
migration we ran. What's the relationship here, do you think?

*Brad Heller *| Director of Engineering | Cloudability.com | 541-231-1514 |
Skype: brad.heller | @bradhe  | @cloudability


We're hiring! https://cloudability.com/jobs



On Sat, Sep 6, 2014 at 10:12 AM, Reindl Harald 
wrote:

>
> Am 06.09.2014 um 19:07 schrieb Brad Heller:
> > For some reason, the history list isn't purging on one of my masters.
> This
> > is causing all kinds of weird issues/behavior with reads
>
> so why do you not just try to update first?
>
> 5.5.39 is recent and contains *a lot* of bufixes
> look at the changelogs - there are tons of replication
> related bugixes with each minor update
>
>

Re: MySQL 5.5.33 History list not purging?

[Reindl Harald]

Am 06.09.2014 um 19:07 schrieb Brad Heller:
> For some reason, the history list isn't purging on one of my masters. This
> is causing all kinds of weird issues/behavior with reads

so why do you not just try to update first?

5.5.39 is recent and contains *a lot* of bufixes
look at the changelogs - there are tons of replication
related bugixes with each minor update



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