Christian Schwarz 8f02bdf96d page cache: improve eviction-related metrics ...

These changes help with identifying thrashing.

The existing `pageserver_page_cache_find_victim_iters_total` is already
useful, but, it doesn't tell us how many individual find_victim() calls
are happening, only how many clock-LRU steps happened in the entire system,
without info about whether we needed to actually evict other data vs
just scan for a long time, e.g., because the cache is large.

The changes in this PR allows us to
1. count each possible outcome separately, esp evictions
2. compute mean iterations/outcome

I don't think anyone except me was paying close attention to
`pageserver_page_cache_find_victim_iters_total` before, so,
I think the slight behavior change of also counting iterations
for the 'iters exceeded' case is fine.

refs https://github.com/neondatabase/cloud/issues/8351
refs https://github.com/neondatabase/neon/issues/5479

2023-12-08 12:57:34 +00:00

..

benches

pageserver: refactor TenantId to TenantShardId in Tenant & Timeline (#5957)

2023-11-29 14:52:35 +00:00

ctl

pagectl: add subcommand to rewrite layer file summary (#5933)

2023-11-30 11:34:30 +00:00

src

page cache: improve eviction-related metrics

2023-12-08 12:57:34 +00:00

test_data

Add walingest test (#5892)

2023-11-28 12:50:53 -05:00

Cargo.toml

refactor: use serde for TenantConf deserialization Fixes: #5300 (#5310)

2023-11-30 12:47:13 +02:00