List:Internals« Previous MessageNext Message »
From:Rick James Date:March 1 2012 9:23pm
Subject:Re: query_cache_type and Aborted Clients
View as plain text  
Which wait_timeout?  There are about 3 -- session vs global and 
interactive versus batch.

query_cache is (probably) totally independent of connections.

Aborted_clients is since startup, and will be "ever increasing" -- 
useless without dividing by something:

Aborted_clients/Uptime -- if > 1, then increase wait_timeout
Aborted_clients/Connections -- if > 30, then increase wait_timeout
Aborted_connects/Uptime -- when this is > 1, you might have a hacker 
trying to get in
Connections/Uptime -- if > 1, you might think about why you need to 
reconnect so often.

If a client sits there too long (more than wait_timeout), he will be 
disconnected.  30 seconds is plenty for web-type applications.

For investigating slow queries, please provide
* SHOW VARIABLES LIKE '%buffer%'; and how much RAM do you have?

On 3/1/12 10:16 AM, Revathi Rangachari wrote:
> Hi
> Can anyone please let me know:
> (1) if query_cache_type is disabled, will it result in the number of 'Aborted
> Clients' getting increased.
> The possible explanation I have is that because the slow queries are taking a long
> time to execute, and the fact that the query_cache_type is also disabled, will it result
> in the clients getting disconnected from the server due to wait_timeout set both at the
> mysql level and application level?
> In my mysql setup the wait_timeout is 30 secs and the query_cache_type is disabled. I
> have an ever increasing number of Aborted Clients
> +------------------+--------+
> | Variable_name    | Value  |
> +------------------+--------+
> | Aborted_clients  | 661117 |
> | Aborted_connects | 156    |
> +------------------+--------+
> The wait_timeout at application level is 5 secs.
> Thanks in advance for any explanation on my query
> Revathi R

Rick James - MySQL Geek

MySQL Audit FunctionAruna Karunarathna5 Feb
  • Re: MySQL Audit FunctionAntony T Curtis5 Feb
    • Re: MySQL Audit FunctionPaul DuBois12 Apr
      • Re: MySQL Audit FunctionAntony T Curtis13 Apr
        • Re: MySQL Audit FunctionPaul DuBois13 Apr
          • RE: MySQL Audit FunctionRick James18 Apr
            • Re: MySQL Audit FunctionSergei Golubchik18 Apr
  • re: MySQL Audit FunctionMichael Widenius21 Feb
    • Re: re: MySQL Audit FunctionSergei Golubchik22 Feb
      • memcache vs.query_cacheRevathi Rangachari23 Feb
        • re: memcache vs.query_cacheMichael Widenius24 Feb
          • re: memcache vs.query_cacheRevathi Rangachari25 Feb
          • Re: memcache vs.query_cacheRick James27 Feb
            • query_cache_type and Aborted ClientsRevathi Rangachari1 Mar
              • Re: query_cache_type and Aborted ClientsRick James1 Mar
                • Re: query_cache_type and Aborted ClientsRevathi Rangachari5 Mar
                  • Re: query_cache_type and Aborted ClientsRick James5 Mar
                    • have_query_cache and query_cache_typeRevathi Rangachari6 Mar
                      • Re: have_query_cache and query_cache_typeYves Trudeau7 Mar
                • Slow query log file not getting updatedRevathi Rangachari20 Mar
                  • Re: Slow query log file not getting updatedBaron Schwartz21 Mar