Clarification of Cache settings

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Based on some discussion on where promotions were limited to only 10%
increased the performance of the cache tier (sorry I can't find that
discussion at the moment to reference). I've been reading through
http://ceph.com/docs/master/rados/operations/cache-tiering/#configuring-a-cache-tier
trying to figure out how to configure this type of promotion and try
different values. I've reviewed the concepts of Bloom filters and so
here are my questions:

1. Is a hit set an individual bloom filter? Or does the bloom filter
keep track of the objects in the cache tier?
2. If each hit set is a Bloom filter... It seems limiting the rate of
promotion could be configured by setting
min_{read,write}_recency_for_promote > 1 (The object would need to be
in more than 1 hit set, where each hit set is 3,600 seconds). But the
documentation specifies "Currently there is minimal benefit for
hit_set_count > 1 since the agent does not yet act intelligently on
that information." My assumption would be to set
min_read,write}_recency_for_promote = 4, set hit_set_count = 15 and
hit_set_period to 300. This would require an object to be accessed at
least in 4 different  5 minute intervals in the last hour to be
promoted. Is this how these values are intended to be used? Does
hit_set_count > 1 still not do anything?
3. I understand that there was some discussion about changing the
tracking for promotion. Will the new method be available in Jewell? Is
the current approach still being developed?

Thanks,


- ----------------
Robert LeBlanc
PGP Fingerprint 79A2 9CA4 6CC4 45DD A904  C70E E654 3BB2 FA62 B9F1
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