diff options
Diffstat (limited to 'src/libstore/gc.cc')
-rw-r--r-- | src/libstore/gc.cc | 88 |
1 files changed, 24 insertions, 64 deletions
diff --git a/src/libstore/gc.cc b/src/libstore/gc.cc index f58f691c99dd..b8395bfc4352 100644 --- a/src/libstore/gc.cc +++ b/src/libstore/gc.cc @@ -1,6 +1,5 @@ #include "globals.hh" #include "misc.hh" -#include "pathlocks.hh" #include "local-store.hh" #include <boost/shared_ptr.hpp> @@ -31,7 +30,7 @@ static const int defaultGcLevel = 1000; read. To be precise: when they try to create a new temporary root file, they will block until the garbage collector has finished / yielded the GC lock. */ -static int openGCLock(LockType lockType) +int LocalStore::openGCLock(LockType lockType) { Path fnGCLock = (format("%1%/%2%") % nixStateDir % gcLockName).str(); @@ -127,7 +126,7 @@ Path addPermRoot(const Path & _storePath, const Path & _gcRoot, Instead of reading all the roots, it would be more efficient to check if the root is in a directory in or linked from the gcroots directory. */ - if (queryBoolSetting("gc-check-reachability", true)) { + if (queryBoolSetting("gc-check-reachability", false)) { Roots roots = store->findRoots(); if (roots.find(gcRoot) == roots.end()) printMsg(lvlError, @@ -136,7 +135,7 @@ Path addPermRoot(const Path & _storePath, const Path & _gcRoot, "therefore, `%2%' might be removed by the garbage collector") % gcRoot % storePath); } - + /* Grab the global GC root, causing us to block while a GC is in progress. This prevents the set of permanent roots from increasing while a GC is in progress. */ @@ -416,18 +415,13 @@ struct LocalStore::GCState PathSet busy; bool gcKeepOutputs; bool gcKeepDerivations; - - bool drvsIndexed; - typedef std::multimap<string, Path> DrvsByName; - DrvsByName drvsByName; // derivation paths hashed by name attribute - - GCState(GCResults & results_) : results(results_), drvsIndexed(false) + GCState(GCResults & results_) : results(results_) { } }; -static bool doDelete(GCOptions::GCAction action) +static bool shouldDelete(GCOptions::GCAction action) { return action == GCOptions::gcDeleteDead || action == GCOptions::gcDeleteSpecific; @@ -441,45 +435,11 @@ bool LocalStore::isActiveTempFile(const GCState & state, && state.tempRoots.find(string(path, 0, path.size() - suffix.size())) != state.tempRoots.end(); } - -/* Return all the derivations in the Nix store that have `path' as an - output. This function assumes that derivations have the same name - as their outputs. */ -PathSet LocalStore::findDerivers(GCState & state, const Path & path) -{ - PathSet derivers; - - Path deriver = queryDeriver(path); - if (deriver != "") derivers.insert(deriver); - - if (!state.drvsIndexed) { - Paths entries = readDirectory(nixStore); - foreach (Paths::iterator, i, entries) - if (isDerivation(*i)) - state.drvsByName.insert(std::pair<string, Path>( - getNameOfStorePath(*i), nixStore + "/" + *i)); - state.drvsIndexed = true; - } - - string name = getNameOfStorePath(path); - - // Urgh, I should have used Haskell... - std::pair<GCState::DrvsByName::iterator, GCState::DrvsByName::iterator> range = - state.drvsByName.equal_range(name); - - for (GCState::DrvsByName::iterator i = range.first; i != range.second; ++i) - if (isValidPath(i->second)) { - Derivation drv = derivationFromPath(i->second); - foreach (DerivationOutputs::iterator, j, drv.outputs) - if (j->second.path == path) derivers.insert(i->second); - } - - return derivers; -} - bool LocalStore::tryToDelete(GCState & state, const Path & path) { + checkInterrupt(); + if (!pathExists(path)) return true; if (state.deleted.find(path) != state.deleted.end()) return true; if (state.live.find(path) != state.live.end()) return false; @@ -508,10 +468,10 @@ bool LocalStore::tryToDelete(GCState & state, const Path & path) then don't delete the derivation if any of the outputs are live. */ if (state.gcKeepDerivations && isDerivation(path)) { - Derivation drv = derivationFromPath(path); - foreach (DerivationOutputs::iterator, i, drv.outputs) - if (!tryToDelete(state, i->second.path)) { - printMsg(lvlDebug, format("cannot delete derivation `%1%' because its output is alive") % path); + PathSet outputs = queryDerivationOutputs(path); + foreach (PathSet::iterator, i, outputs) + if (!tryToDelete(state, *i)) { + printMsg(lvlDebug, format("cannot delete derivation `%1%' because its output `%2%' is alive") % path % *i); goto isLive; } } @@ -522,18 +482,9 @@ bool LocalStore::tryToDelete(GCState & state, const Path & path) if (!pathExists(path)) return true; /* If gc-keep-outputs is set, then don't delete this path if - its deriver is not garbage. !!! Nix does not reliably - store derivers, so we have to look at all derivations to - determine which of them derive `path'. Since this makes - the garbage collector very slow to start on large Nix - stores, here we just look for all derivations that have the - same name as `path' (where the name is the part of the - filename after the hash, i.e. the `name' attribute of the - derivation). This is somewhat hacky: currently, the - deriver of a path always has the same name as the output, - but this might change in the future. */ + there are derivers of this path that are not garbage. */ if (state.gcKeepOutputs) { - PathSet derivers = findDerivers(state, path); + PathSet derivers = queryValidDerivers(path); foreach (PathSet::iterator, deriver, derivers) { /* Break an infinite recursion if gc-keep-derivations and gc-keep-outputs are both set by tentatively @@ -567,7 +518,7 @@ bool LocalStore::tryToDelete(GCState & state, const Path & path) } /* The path is garbage, so delete it. */ - if (doDelete(state.options.action)) { + if (shouldDelete(state.options.action)) { printMsg(lvlInfo, format("deleting `%1%'") % path); unsigned long long bytesFreed, blocksFreed; @@ -613,6 +564,15 @@ void LocalStore::collectGarbage(const GCOptions & options, GCResults & results) state.gcKeepOutputs = queryBoolSetting("gc-keep-outputs", false); state.gcKeepDerivations = queryBoolSetting("gc-keep-derivations", true); + + /* Using `--ignore-liveness' with `--delete' can have unintended + consequences if `gc-keep-outputs' or `gc-keep-derivations' are + true (the garbage collector will recurse into deleting the + outputs or derivers, respectively). So disable them. */ + if (options.action == GCOptions::gcDeleteSpecific && options.ignoreLiveness) { + state.gcKeepOutputs = false; + state.gcKeepDerivations = false; + } /* Acquire the global GC root. This prevents a) New roots from being added. @@ -667,7 +627,7 @@ void LocalStore::collectGarbage(const GCOptions & options, GCResults & results) vector<Path> entries_(entries.begin(), entries.end()); random_shuffle(entries_.begin(), entries_.end()); - if (doDelete(state.options.action)) + if (shouldDelete(state.options.action)) printMsg(lvlError, format("deleting garbage...")); else printMsg(lvlError, format("determining live/dead paths...")); |