we need to skip the SIP region in the last step of handling the alloc region

[Maoni0]

in process_remaining_regions, if we haven't gone through the while loop to handle the regions with pinned plugs, we can end up with current_region being an SIP region. then we mistakenly call decide_on_demotion_pin_surv which can change its planned generation. I'm filtering this out before we call decide_on_demotion_pin_surv because the pinned survival in an SIP region is always 0 so we wouldn't want decide_on_demotion_pin_surv to treat it as "to be empty".

thanks very much, @kevingosse, for reporting this!

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Issue Details

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in process_remaining_regions, if we haven't gone through the while loop to handle the regions with pinned plugs, we can end up with current_region being an SIP region. then we mistakenly call decide_on_demotion_pin_surv which can change its planned generation. I'm filtering this out before we call decide_on_demotion_pin_surv because the pinned survival in an SIP region is always 0 so we wouldn't want decide_on_demotion_pin_surv to treat it as "to be empty".

thanks very much, @kevingosse, for reporting this!

Author:	Maoni0
Assignees:	Maoni0
Labels:	area-GC-coreclr
Milestone:	-

[teo-tsirpanis]

I've been wondering, what is SIP?

[Maoni0]

SIP stands for Swept In Plan - those are special regions that are swept during a compacting GC because the survival rate is very high on them. they are disabled by default as they might increase your heap size noticeably.

[teo-tsirpanis]

Thanks!

[cshung]

LGTM