What triggers L2 cache flush? Topic is solved

[Magistar]

I noticed that today my cache hit rate is only 32%. Closer inspection showed that 98 GB of L2 cache is free, the L2 partition is 115 GB.
Since I use 10% for write cache this means almost no data is in the L2 cache. The write cache is only 32 MB free. So it appears the write cache is not emptying itself over time. I now adjusted to 15% write cache and 5 GB is now free in write.

What is going on? Can this be caused by 0 MB l1 cache?

cfg export:

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[Support]

The cache space finally will get full. But this is not a problem. It just tells you the all cache space has data cached. PrimoCache will automatically runs the cache algorithm, replacing outdated cache data by new incoming data. There's no need to free cache content when the cache space is full, because old cache content will be replaced.

And regarding the L2 cache reset, was there an abnormal shutdown before? PrimoCache L2 has a verify mechanism to ensure the integrity of the cache data. If there's an abnormal shutdown, PrimoCache will reset L2 cache.

[Magistar]

Ok thanks for clarifying. But then how can I verify the write cache is actually working?

Regarding L2, not about the shutdown. Will keep an eye on it.

[Support]

I assume you enable the defer-write since you use the write cache. You may check the statistics "Total Write (Req)", "Total Write (L1/L2)", "Total Write (Disk)" and "Deferred Blocks". When the defer-write is enabled, if you write a file to the target volume, you will see "Total Write (Req)" and "Total Write (L1/L2)" increases, but Total Write (Disk) keeps unchanged. You will also see "Deferred Blocks" increases. These indicate that the file is written to L1/L2 cache first and is deferred to write to the target volume.

[RAMbo]

And regarding the L2 cache reset, was there an abnormal shutdown before? PrimoCache L2 has a verify mechanism to ensure the integrity of the cache data. If there's an abnormal shutdown, PrimoCache will reset L2 cache.

Does that mean usually L2 isn't flushed on a reboot? Is the documentation outdated?
http://www.romexsoftware.com/en-us/fancy-cache/faq.html

Q: Is L2 Cache data persistent across computer restarts?

A: No. Currently it is not.

[Jaga]

Does that mean usually L2 isn't flushed on a reboot? Is the documentation outdated?
http://www.romexsoftware.com/en-us/fancy-cache/faq.html

Fancycache is the older product, now renamed and called Primocache. That FAQ is outdated. See the current Primocache FAQ for the right information: http://www.romexsoftware.com/en-us/prim ... ation.html

If you enable Volatile Cache Contents, Primocache will flush at reboot time. If you disable it, L2 cache contents are preserved across reboots.

Volatile Cache Contents: Cache contents in the level-2 storage are not preserved when the system is rebooted. This option is usually for multi-boot computers where another operating system may modify cached volumes, leading to the inconsistency between cache contents and source data.

[RAMbo]

Aaaaarrrrgh, I didn't even notice it was about FancyCache. I found the statement when Googling for L2 in PrimoCache.
Mystery solved. Thanks!