On Tue, May 31, 2022 at 9:12 PM David G. Johnston < david.g.johns...@gmail.com> wrote:
> On Tuesday, May 31, 2022, Praneel Devisetty <devisettypran...@gmail.com> > wrote: > >> >> Initially it was processing 1000 tables per minute. Performance is >>> gradually dropping and now after 24 hr it was processing 90 tables per >>> minute. >>> >> > That seems like a fairly problematic metric given the general vast > disparities in size tables have. > > Building indexes is so IO heavy that the non-IO bottlenecks that exists > likely have minimal impact on the overall times this rebuild everything > will take. That said, I’ve never done anything at this scale before. I > wouldn’t be too surprised if per-session cache effects are coming into play > given the number of objects involved and the assumption that each session > used for parallelism is persistent. I’m not sure how the parallelism works > for managing the work queue though as it isn’t documented and I haven’t > inspected the source code. > could you please share more about per-session cache effects /Point me to link with more info .
