Add ZABBIX calculation type itemcalculated items

adopt Redis Self contained info Command can monitor keyspace_hits and keyspace_misses These two values , however redis The hit rate of cannot be obtained directly , Can pass zabbix Of calculated items Implementation monitoring redis shooting

https://www.zabbix.com/documentation/2.2/manual/config/items/itemtypes/calculated

zabbix from 1.8.1 Start to support this function

In New item when , Need to choose type by Calculated.

stay Key Fill in the new column key The name of

stay Formula Fill in new key The calculation expression of

func(<key>|<hostname:key>,<parameter1>,<parameter2>,...)

func yes https://www.zabbix.com/documentation/2.2/manual/appendix/triggers/functions Functions supported in the document

key It is other things that need to be used item, Better use double quotation marks "" take key Value expansion , If key If there are quotation marks in the middle of the value, you need to use \ escape .

parameter Other parameters that need to be used

Example ：

1.zabbix Calculate the ratio of the latest free disk space to the total disk space .

 100*last("vfs.fs.size[/,free]",0)/last("vfs.fs.size[/,total]",0)

2. Calculate the average 10 Within minutes zabbix Processed values

  avg("Zabbix Server:zabbix[wcache,values]",600)

  Calculation type item, If the acquisition interval is too long, it will affect zabbix server Performance of

3. Calculation eth0 Total bandwidth

  last("net.if.in[eth0,bytes]",0)+last("net.if.out[eth0,bytes]",0)

4. Calculate the proportion of inlet flow

  100*last("net.if.in[eth0,bytes]",0)/(last("net.if.in[eth0,bytes]",0)+last("net.if.out[eth0,bytes]",0))

5.

last("grpsum[\"video\",\"net.if.out[eth0,bytes]\",\"last\",\"0\"]",0) / last("grpsum[\"video\",\"nginx_stat.sh[active]\",\"last\",\"0\"]",0) 

After testing, if Formula There are macro definitions in the expression, such as {#REDISPORT}, The whole expression needs parentheses () Expansion . So when adding an expression, you can use the whole expression () Expansion , Whether or not there is a macro definition .