Commit Graph

18 Commits

Author SHA1 Message Date
David Goldblatt
47d8a7e6b0 psset: Purge empty slabs first.
These are particularly good candidates for purging (listed in the diff).
2021-07-12 17:59:18 -07:00
David Goldblatt
41fd56605e HPA: Purge across retained extents.
This lets us cut down on the number of expensive system calls we perform.
2021-07-12 17:59:18 -07:00
David Goldblatt
73ca4b8ef8 HPA: Use dirtiest-first purging.
This seems to be practically beneficial, despite some pathological corner cases.
2021-02-19 15:10:54 -08:00
David Goldblatt
d21d5b46b6 Edata: Move sn into its own field.
This lets the bins use a fragmentation avoidance policy that matches the HPA's
(without affecting the PAC).
2021-02-19 15:10:54 -08:00
David Goldblatt
9fd9c876bb psset: keep aggregate stats.
This will let us quickly query these stats to make purging decisions quickly.
2021-02-04 20:58:31 -08:00
David Goldblatt
bf64557ed6 Move empty slab tracking to the psset.
We're moving towards a world in which purging decisions are less rigidly
enforced at a single-hugepage level.  In that world, it makes sense to keep
around some hpdatas which are not completely purged, in which case we'll need to
track them.
2021-02-04 20:58:31 -08:00
David Goldblatt
99fc0717e6 psset: Reconceptualize insertion/removal.
Really, this isn't a functional change, just a naming change.  We start thinking
of pageslabs as being always in the psset.  What we used to think of as removal
is now thought of as being in the psset, but in the process of being updated
(and therefore, unavalable for serving new allocations).

This is in preparation of subsequent changes to support deferred purging;
allocations will still be in the psset for the purposes of choosing when to
purge, but not for purposes of allocation/deallocation.
2021-02-04 20:58:31 -08:00
David Goldblatt
be0d7a53f3 HPA: Don't track inactive pages.
This is really only useful for human consumption.  Correspondingly, emit it only
in the human-readable stats, and let everybody else compute from the hugepage
size and nactive.
2021-02-04 20:58:31 -08:00
David Goldblatt
55e0f60ca1 psset stats: Simplify handling.
We can treat the huge and nonhuge cases uniformly using huge state as an array
index.
2021-02-04 20:58:31 -08:00
David Goldblatt
f51948d9e1 psset unit test: fix a bug.
The next commit adds assertions that reveal a bug in the test code
(double-free).  Fix it.
2020-12-07 06:21:08 -08:00
David Goldblatt
f7cf23aa4d psset: Relegate alloc/dalloc to test code.
This is no longer part of the "core" functionality; we only need the stub
implementations as an end-to-end test of hpdata + psset interactions when
metadata is being modified.  Treat them accordingly.
2020-12-07 06:21:08 -08:00
David Goldblatt
ca30b5db2b Introduce hpdata_t.
Using an edata_t both for hugepages and the allocations within those hugepages
was convenient at first, but has outlived its usefulness.  Representing
hugepages explicitly, with their own data structure, will make future
development easier.
2020-12-07 06:21:08 -08:00
David Goldblatt
43af63fff4 HPA: Manage whole hugepages at a time.
This redesigns the HPA implementation to allow us to manage hugepages all at
once, locally, without relying on a global fallback.
2020-12-07 06:21:08 -08:00
David Goldblatt
c1b2a77933 psset: Move in stats.
A later change will benefit from having these functions pulled into a
psset-module set of functions.
2020-12-07 06:21:08 -08:00
David Goldblatt
d0a991d47b psset: Add insert/remove functions.
These will allow us to (for instance) move pageslabs from a psset dedicated to
not-yet-hugeified pages to one dedicated to hugeified ones.
2020-12-07 06:21:08 -08:00
David Goldblatt
d16849c91d psset: Do first-fit based on slab age.
This functions more like the serial number strategy of the ecache and
hpa_central_t.  Longer-lived slabs are more likely to continue to live for
longer in the future.
2020-10-23 11:14:34 -07:00
David Goldblatt
259c5e3e8f psset: Add stats 2020-09-18 12:39:25 -07:00
David Goldblatt
018b162d67 Add psset: a set of pageslabs.
This introduces a new sort of edata_t; a pageslab, and a set to manage them.
This is part of a series of a commits to implement a hugepage allocator; the
pageset will be per-arena, and track small page allocations requests within a
larger extent allocated from a centralized hugepage allocator.
2020-09-18 12:39:25 -07:00