* Wrap deleteFromStore() in a transaction. Otherwise there might be a

race with other processes that add new referrers to a path,
  resulting in the garbage collector crashing with "foreign key
  constraint failed".  (Nix/4)
* Make --gc --print-dead etc. interruptible.
This commit is contained in:
Eelco Dolstra 2010-10-14 15:55:51 +00:00
parent bfa6ee7d91
commit 64fd29855a
2 changed files with 13 additions and 8 deletions

View file

@ -421,7 +421,7 @@ struct LocalStore::GCState
};
static bool doDelete(GCOptions::GCAction action)
static bool shouldDelete(GCOptions::GCAction action)
{
return action == GCOptions::gcDeleteDead
|| action == GCOptions::gcDeleteSpecific;
@ -438,6 +438,8 @@ bool LocalStore::isActiveTempFile(const GCState & state,
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;
@ -516,7 +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;
@ -625,7 +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..."));

View file

@ -298,11 +298,10 @@ void LocalStore::openDB(bool create)
if (sqlite3_exec(db, ("pragma synchronous = " + syncMode + ";").c_str(), 0, 0, 0) != SQLITE_OK)
throw SQLiteError(db, "setting synchronous mode");
/* Set the SQLite journal mode. The default is write-ahead
logging since it's the fastest and supports more concurrency.
The downside is that it doesn't work over NFS, so allow
truncate mode alternatively. */
string mode = queryBoolSetting("use-sqlite-wal", true) ? "wal" : "truncate";
/* Set the SQLite journal mode. WAL mode is fastest, but doesn't
seem entirely stable at the moment (Oct. 2010). Thus, use
truncate mode by default. */
string mode = queryBoolSetting("use-sqlite-wal", false) ? "wal" : "truncate";
string prevMode;
{
SQLiteStmt stmt;
@ -1220,6 +1219,8 @@ void LocalStore::deleteFromStore(const Path & path, unsigned long long & bytesFr
assertStorePath(path);
SQLiteTxn txn(db);
if (isValidPath(path)) {
PathSet referrers; queryReferrers(path, referrers);
referrers.erase(path); /* ignore self-references */
@ -1230,6 +1231,8 @@ void LocalStore::deleteFromStore(const Path & path, unsigned long long & bytesFr
}
deletePathWrapped(path, bytesFreed, blocksFreed);
txn.commit();
}