Alexey, If to rephrase it differently, if a cache/table belongs to a single cache group then its entries will never be mixed with the entries of another caches/tables in both data and index pages. Please confirm that my statement is correct. Also, does that counter accumulates size of BinaryObjects or the whole data/index pages?
Finally, do you plan to rework CacheMetrics.getOffHeapAllocatedSize method for this purpose? (btw, to my knowledge the method is broken at the moment and returns 0). -- Denis On Thu, Mar 29, 2018 at 1:20 AM, Alexey Goncharuk < alexey.goncha...@gmail.com> wrote: > Denis, > > Currently there is an easy way to add per-cache-group metrics for data and > index pages. There is an internal counter, but it is not published as an > MBean metric, we will do this as a part of IEP-6. > > As for the per-cache metrics, this can be implemented, but it will take a > significantly greater effort and most likely will affect performance. As > Andrey noted, when two caches share the same cache group, multiple entries > may be written to the same page, this needs special handling. I suggest we > first start with per-cache-group metrics and then, if there is high demand, > start thinking about per-cache metrics. > > --AG > > 2018-03-27 15:18 GMT+03:00 Andrey Kuznetsov <stku...@gmail.com>: > > > I apologize for the previous message sent in hurry. It's imposible to > > measure the difference between 'precise' and 'estimated' page memory > usage > > per cache unless we fully implement approach 2. Current model allows to > > store objects from several caches in a single page. > > > > 2018-03-23 22:21 GMT+03:00 Andrey Kuznetsov <stku...@gmail.com>: > > > > > Denis, > > > > > > I'll need to conduct some experiments to estimate the difference. And > the > > > answer will depend on numerous parameters: object sizes, number of > > caches, > > > that share the same data region and so on. > > > > > > пт, 23 марта 2018, 21:53 Denis Magda <dma...@apache.org>: > > > > > >> Andrey, > > >> > > >> How good will be the estimate if we go for 1. and utilize > > pagesFillFactor > > >> somehow? In other words, how big can be a difference between 100% > > precise > > >> calculation you the approach you're suggesting? > > >> > > >> -- > > >> Denis > > >> > > >> > > > > > > -- > > Best regards, > > Andrey Kuznetsov. > > >
