f56bf754_WebStorm_10_0_0_Help____Tasks__Description
[Item] Enable issue cache [Description] 
Select this check box to have WebStorm synchronize with the issue tracking system in the background on a regular basis, No matter whether you actually request on information from your issue tracker or not, WebStorm will connect to your issue tracking system according to the specified frequency and refresh the cached issues. The advantage of this approach is that when you need to switch to a task, the up-to-date information is already at your disposal so you do not need to wait till WebStorm establishes connection with the tracker and retrieves the information. This configuration is especially recommended when working with rather "slow" issue tracking systems. Clear this check box to have WebStorm connect to the issue tracking system only when you actually need information on issues, clear the Enable issue cache check box.
WebStorm 10.0.0 Help :: Tasks