Hi, 1. It looks weird, yeah. Need to ask Sergey, who has changed it last time.
2. Because we could reuse memory. For example, after cache destroy or something like that. On Tue, Jun 19, 2018 at 9:58 PM, John Wilson <sami.hailu...@gmail.com> wrote: > Hi, > > Two quick questions: > > > 1. The design documentation here, > https://cwiki.apache.org/confluence/display/IGNITE/ > Ignite+Durable+Memory+-+under+the+hood, > states that the default segment count is equal to the number of logical > cores available in the underlying machine. However, the segments array > in > PageMemory indicates that the maximum number of segments is: 1 << > SEG_BITS. > Since SEG_BITS = 4, the max # segments is 16. Did I miss something here? > 2. Reading the code in PageMemoryNoStoreImp, it looks like pages are > allocated segment sequentially in a bump-the-pointer strategy where the > first 8 bytes of a segment hold a pointer to the index of the last > allocated page. If this is true, then I don't understand the point of > having a page map buckets. Why not use a simple arithmetic index * > pageSize > to get the offset of a page? > > Thanks. > John >
