FAQ
Which Yocto releases does it work with?
Section titled “Which Yocto releases does it work with?”The meta-yocache layer declares compatibility with every release from
dunfell through the current wrynose (dunfell, gatesgarth, hardknott,
honister, kirkstone, langdale, mickledore, nanbield, scarthgap, styhead,
walnascar, wrynose). Dunfell, kirkstone, and wrynose are build-tested
end-to-end; the releases in between share the same code paths as one of
those three, so they’re covered too. The optional hash-equivalence
integration works on every supported release: bitbake’s WebSocket transport
requires scarthgap or newer (ws://yourcache.local:6768/hashequiv), and
older releases — whose hash-equivalence client has no ws:// support — use
the server’s raw-TCP listener instead (yourcache.local:6767, on by
default). See Client configuration for the
BB_HASHSERVE values.
Can a cache problem break my build?
Section titled “Can a cache problem break my build?”No — that’s a design rule, not an accident. A cache miss means bitbake falls back to upstream sources and local building, exactly as without YoCache. And if the server is unreachable or an upload fails, the build carries on and you get at most a warning. YoCache only ever makes builds faster, never redder.
What happens when the disk fills up?
Section titled “What happens when the disk fills up?”Give the server a --quota (say, 500GiB) and an eviction policy
(--evict lru), and it frees space on demand by dropping the artifacts
nobody has touched for the longest time. The cache stays within budget
without anyone cleaning it manually.
One recipe produces broken sstate — do I have to flush the whole cache?
Section titled “One recipe produces broken sstate — do I have to flush the whole cache?”No. Start the server with --block-recipe <name> and the cache refuses to
store or serve that recipe’s sstate while everything else keeps flowing.
Repeat the flag for multiple recipes.
Is it safe to point many machines at one server?
Section titled “Is it safe to point many machines at one server?”Yes — that’s the intended setup. Uploads are written atomically, so a reader never sees a half-uploaded artifact, and concurrent uploads of the same artifact resolve cleanly.
Do I need a database or other services?
Section titled “Do I need a database or other services?”No. The server is one static binary; its operational state lives in a single SQLite file it manages itself. There is nothing else to install, and moving the cache to another machine is a matter of copying a directory.