1107310 - Mention max_allowed_packet in mysqldump section

Status: RESOLVED FIXED

(Bugzilla :: Documentation, defect)

Description

[Gervase Markham [:gerv]]

http://bugzilla.readthedocs.org/en/latest/installing/backups.html - section 3.10.1.1 should mention the max_allowed_packet parameter that you sometimes need on the command line to do a mysqldump.

Gerv

Comment 1

[Gervase Markham [:gerv]]

Attachment: Patch v.1

Comment 2

[Frédéric Buclin]

Comment on attachment 8569210 [details] [diff] [review]
Patch v.1

>+:command:`mysqldump --opt --max-allowed-packet=16M -u $USERNAME -p $DATABASENAME > backup.sql`

No need to pass --opt. It's enabled by default. Also, the default value for max-allowed-packet is 24MB. It's a bit weird to ask admins to use a lower value when doing backups.

Comment 3

[Gervase Markham [:gerv]]

(In reply to Frédéric Buclin from comment #2)
> Comment on attachment 8569210 [details] [diff] [review]
> Patch v.1
> 
> >+:command:`mysqldump --opt --max-allowed-packet=16M -u $USERNAME -p $DATABASENAME > backup.sql`
> 
> No need to pass --opt. It's enabled by default. 

OK.

> Also, the default value for
> max-allowed-packet is 24MB. It's a bit weird to ask admins to use a lower
> value when doing backups.

16M is the value we suggest in the install docs, which is why I'm using it as the example here. 

I too thought the default value was higher, and so hoped to eliminate the requirement to set it entirely from the docs, but then I was told that it varied from distribution to distribution.

Is there any harm in setting it to way higher than the DB uses? E.g. 512M?

Gerv

Comment 4

[Frédéric Buclin]

(In reply to Gervase Markham [:gerv] from comment #3)
> Is there any harm in setting it to way higher than the DB uses? E.g. 512M?

(Almost) nobody wants to store attachments as large as 512MB in the DB. Just set it to 24MB or 32MB if you want a sensible example.

Comment 5

[Frédéric Buclin]

Comment on attachment 8569210 [details] [diff] [review]
Patch v.1

Please fix comment 4.

Comment 6

[Gervase Markham [:gerv]]

Attachment: Patch v.2

Comment 7

[Frédéric Buclin]

Comment on attachment 8570460 [details] [diff] [review]
Patch v.2

I didn't try to compile the documentation, but it looks good. r=LpSolit

Comment 8

[Gervase Markham [:gerv]]

To ssh://[e-mail]/bugzilla/bugzilla.git
   b7147b7..c33b98d  master -> master

To ssh://[e-mail]/bugzilla/bugzilla.git
   c1fa559..dd15f45  5.0 -> 5.0

Gerv