pg autoscale on EC pools
The pg_autoscaler plugin wants to seriously increase num_pg on my EC pool from 8192 to 65536, but it seems it doesn't account for the extra shards created on other OSDS which leads to much more PG-per-OSD as configured at 100.
For example, I've got 624 osds with 8192 pg_num on the EC 6+2 pool. My calculation is that this results in (6+2)*8192 / 624 = ~105 PG-per-OSD (which is also observed).
Following the pg_autoscaler suggestion this would lead to 65536 PG's and ~840 PG-per-osd, which seems crazy.
Can anyone explain what I am missing here or is this a autoscaler miscalculation? The logic it uses is the size 1.33 (33% overhead) which it uses to calculate an expected 1.33 * 65536 / 624 = ~139 PG-per-OSD.