check_memcached

                                

        
        

            
            

                

    

    
check_memcached


check_memcached will give a critical message if a partiular memcached host is inaccessible.


It will generate a warning (only) if the hit/miss ratio falls below a given threshold (default 2)
It will generate a warning (only) if the number of evictions exceeds a given limit (default 10)


Hit/miss and evictions are measured over a 30 minute interval, using a memcached object to store the earlier statistics.
Almost ALL other check_memcached plugins just quote the raw stats, which are measured from when the daemon was last started.
By distinction, this plugin measures the hit/miss ratio over a well-defined time-interval (by default the last 30 minutes)


The thresholds for the hit/miss ratio and eviction-rate may be specified on the command line.
The measurement time-interval may also be specified on the command line (this interval is also used for the performance data)


Set $memcached_graph_composite = 0 to plot 4 graphs:


    

  • 1st graph: gets and hits
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  • 2nd graph: sets and misses
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  • 3rd graph: hit/miss ratio
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  • 4th graph: evictions
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Set $memcached_graph_composite = 1 to plot 2 graphs:


    

  • 1st graph: has gets and hits in the positive direction, and sets, misses and evictions in the negative direction
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  • 2nd graph: is hit/miss ratio on it's own
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This plugin is written in C and also requires:
 Flex: http://flex.sourceforge.net/
 libmemcached: http://libmemcached.org/libMemcached.html


    

  • v1.3 added rate-based performance statistics for better pnp4nagios integration (-r option)
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