twitter / fatcache

Memcache on SSD
Apache License 2.0
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Writing to disk on GETs #14

Open annief opened 10 years ago

annief commented 10 years ago

Hi, I noticed that GETs do not result in writes to the disk. This makes sense for the common case.

I'm wondering if there are cases where fatcache would be required to write to disk in the future? e.g. support CAS, maintain state of cache across power cycle.

BTW, Is there a plan to support "persistent" fatcache that keeps state across power cycle? Is a persistent memcache useful in real deployments?

Thanks.

manjuraj commented 10 years ago

"persistent fatcache" does make sense. However, it would be difficult to achieve throughputs and latency similar to in-memory memcache because every read/write would go to ssd. This would make it persistent fatcache is non-viable replacement for in-memory memcache.