Improve addrman Select() performance when buckets are nearly empty #6530
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| @@ -341,8 +341,11 @@ CAddrInfo CAddrMan::Select_() | |||
| while (1) { | |||
| int nKBucket = GetRandInt(ADDRMAN_TRIED_BUCKET_COUNT); | |||
| int nKBucketPos = GetRandInt(ADDRMAN_BUCKET_SIZE); | |||
| if (vvTried[nKBucket][nKBucketPos] == -1) | |||
| continue; | |||
| while (1) { | |||
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Equivalent but maybe slightly more readable:
while(vvTried[nKBucket][nKBucketPos] == -1) {
nKBucket = (nKBucket + insecure_rand()) % ADDRMAN_TRIED_BUCKET_COUNT;
nKBucketPos = (nKBucketPos + insecure_rand()) % ADDRMAN_BUCKET_SIZE;
}
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laanwj
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Aug 26, 2015
c33c11e Improve addrman Select() performance when buckets are nearly empty (Pieter Wuille)
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Earlier, when there are only a few entries in the addrman tables, Select() could spin for long periods of time (~200ms), resulting in high CPU usage (up to 40% here). This reduces it to around 0.3ms (0.5% CPU).