Subscribe

Clean flash cache contents

[ Edited ]

How to clean (dump, remove) flash cache contents? Seems flash cache was enabled during testing phase and filled with a lot of useless data. I want to dump the content and start caching real production data.

Clean flash cache contents

The content on the card ages itself out and gets replaced by the new content automatically like any other cache you can see the speed it inserting new and deleting old content with the "stats show -p flexscale-access" there are metrics about invalidates and evictions per second as well as information on your hit and miss ratio

If you wanted to force it you could ether disable the cards or probably the safer option would be to do a takeove and giveback of each head. The Cache flushes and has to re-warm after a takeover and giveback.

Clean flash cache contents

If by 'disabling card' means running options flexscale.enable off and options flexcache.enable off commands, it does not work, already tried:

stats show -p flexscale-access

Cache                                               Reads       Writes      Disk Reads

Usage    Hit   Meta   Miss Hit Evict Inval Insert Chain Blocks Chain Blocks  Replaced

     %     /s     /s     /s   %    /s    /s     /s    /s     /s    /s     /s        /s

    98      0      0      0   0     0     0      0     0      0     0      0         0

    98      0      0      0   0     0     0      0     0      0     0      0         0

    98      0      0      0   0     0     0      0     0      0     0      0         0

    98      0      0      0   0     0     0      0     0      0     0      0         0

    98      0      0      0   0     0     0      0     0      0     0      0         0

Clean flash cache contents

UP, anybody?

4 days have passed since I disabled flash cache, if cache contents age and are cleaned up automatically it should be already cleaned up but it is not the case. Here is the output from the both filers:

stats show -p flexscale-access

Cache                                               Reads       Writes      Disk Reads

Usage    Hit   Meta   Miss Hit Evict Inval Insert Chain Blocks Chain Blocks  Replaced

     %     /s     /s     /s   %    /s    /s     /s    /s     /s    /s     /s        /s

    82      0      0      0   0     0     0      0     0      0     0      0         0

    82      0      0      0   0     0     0      0     0      0     0      0         0

    82      0      0      0   0     0     6      0     0      0     0      0         0

    82      0      0      0   0     0     0      0     0      0     0      0         0

stats show -p flexscale-access

Cache                                               Reads       Writes      Disk Reads

Usage    Hit   Meta   Miss Hit Evict Inval Insert Chain Blocks Chain Blocks  Replaced

     %     /s     /s     /s   %    /s    /s     /s    /s     /s    /s     /s        /s

    98      0      0      0   0     0     0      0     0      0     0      0         0

    98      0      0      0   0     0     0      0     0      0     0      0        

Clean flash cache contents

I doubt cache usage will go to 0% by just disabling the flash cache. What happens with the usage when you turn it on again?

Anyway, as Jered already mentioned old/stale data will be automatically removed from cache when there is new data that needs to be cached.