Code bug

[haiheipijuan]

Version/Platform/Processor information (from ipfs version --all):
go-ipfs version: 0.4.3-rc2-3ba9b67
Repo version: 4
System version: amd64/darwin
Golang version: go1.6

Type (bug, feature, meta, test failure, question):bug
Area (api, commands, daemon, fuse, etc):code
Priority (from P0: functioning, to P4: operations on fire):p1

Description:
code is here: https://github.com/ipfs/go-ipfs/blob/master/blocks/blockstore/arc_cache.go#L63, shoud be "if res {", because we don't need to to put the key into the cache does not exist.

[Kubuxu]

I disagree with your statement, we want to cache both positive and negative Has responses. This means: if Has call was successful, put it into cache, no matter if it is true or false.

The bloom filter cache is currently disabled by default so it will be unable to catch cases in which the Has response is false.

In future we should place active bloom filter cache before ARC cache to reduce number of hits to ARC.

[haiheipijuan]

OK, thanks.