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57ce203 fuzz: allow lower number of sources (Martin Zumsande)
acf656d fuzz: Use public interface to fill addrman tried tables (Martin Zumsande)
eb2e113 addrman: Improve performance of Good (Martin Zumsande)
Pull request description:
Currently, `CAddrman::Good()` is rather slow because the process of moving an addr from new to tried involves looping over the new tables twice:
1) In `Good_()`, there is a loop searching for a new bucket the addr is currently in, but this information is never used except for aborting if it is not found anywhere (since [this commit](bitcoin/bitcoin@e6b343d#diff-49d1faa58beca1ee1509a247e0331bb91f8604e30a483a7b2dea813e6cea02e2R263) it is no longer passed to `MakeTried`)
This is unnecessary because in a non-corrupted addrman, an address that is not in New must be either in Tried or not at all in addrman, both cases in which we'd return early in `Good_()` and never get to this point.
I removed this loop (and left a check for `nRefCount` as a belt-and-suspenders check).
2) In `MakeTried()`, which is called from `Good_()`, another loop removes all instances of this address from new. This can be spedup by stopping the search at `nRefCount==0`. Further reductions in `nRefCount` would only lead to an assert anyway.
Moreover, the search can be started at the bucket determined by the source of the addr for which `Good` was called, so that if it is present just once in New, no further buckets need to be checked.
While calls to `Good()` are not that frequent normally, the performance gain is clearly seen in the fuzz target `addman_serdeser`, where, because of the slowness in creating a decently filled addrman, a shortcut was created that would directly populate the tried tables by reaching into addrman's internals, bypassing `Good()` (#21129).
I removed this workaround in the second commit: Using `Good()` is still slower by a factor of 2 (down from a factor of ~60 before), but I think that this compensated by the advantages of not having to reach into the internal structures of addrman (see jnewbery/bitcoin#18 (comment)).
[Edit]: For benchmark results see bitcoin/bitcoin#22974 (comment) and bitcoin/bitcoin#22974 (comment) - the benchmark `AddrManGood` shows a significant speedup by a factor >100.
ACKs for top commit:
naumenkogs:
ACK 57ce203
jnewbery:
ACK 57ce203
laanwj:
Code review ACK 57ce203
theStack:
ACK 57ce203
vasild:
ACK 57ce203
Tree-SHA512: fb6dfc198f2e28bdbb41cef9709828f22d83b4be0e640a3155ca42e771b6f58466de1468f54d773e794f780a79113f9f7d522032e87fdd75bdc4d99330445198
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