Use a thread per connection
This commit is contained in:
Eelco Dolstra
parent
ff453b06f9
commit
262520fcfe
|
|
@ -636,6 +636,7 @@ void LocalStore::removeUnusedLinks(const GCState & state)
|
|||
}
|
||||
|
||||
|
||||
|
||||
void LocalStore::collectGarbage(const GCOptions & options, GCResults & results)
|
||||
{
|
||||
GCState state(options, results);
|
||||
|
|
@ -674,83 +675,75 @@ void LocalStore::collectGarbage(const GCOptions & options, GCResults & results)
|
|||
shutdownPipe.create();
|
||||
|
||||
std::thread serverThread([&]() {
|
||||
std::map<int, std::pair<std::unique_ptr<AutoCloseFD>, std::string>> fdClients;
|
||||
bool quit = false;
|
||||
Sync<std::map<int, std::thread>> connections;
|
||||
std::atomic_bool quit = false;
|
||||
|
||||
while (!quit) {
|
||||
Finally cleanup([&]() {
|
||||
debug("GC roots server shutting down");
|
||||
while (true) {
|
||||
auto item = remove_begin(*connections.lock());
|
||||
if (!item) break;
|
||||
auto & [fd, thread] = *item;
|
||||
shutdown(fd, SHUT_RDWR);
|
||||
thread.join();
|
||||
}
|
||||
});
|
||||
|
||||
while (true) {
|
||||
std::vector<struct pollfd> fds;
|
||||
fds.push_back({.fd = shutdownPipe.readSide.get(), .events = POLLIN});
|
||||
fds.push_back({.fd = fdServer.get(), .events = POLLIN});
|
||||
for (auto & i : fdClients)
|
||||
fds.push_back({.fd = i.first, .events = POLLIN});
|
||||
auto count = poll(fds.data(), fds.size(), -1);
|
||||
assert(count != -1);
|
||||
|
||||
for (auto & fd : fds) {
|
||||
if (!fd.revents) continue;
|
||||
if (fd.fd == shutdownPipe.readSide.get())
|
||||
/* Parent is asking us to quit. */
|
||||
quit = true;
|
||||
else if (fd.fd == fdServer.get()) {
|
||||
/* Accept a new connection. */
|
||||
assert(fd.revents & POLLIN);
|
||||
auto fdClient = std::make_unique<AutoCloseFD>(accept(fdServer.get(), nullptr, nullptr));
|
||||
if (*fdClient) {
|
||||
auto fd = fdClient->get();
|
||||
fdClients.insert({fd, std::make_pair(std::move(fdClient), "")});
|
||||
if (fds[0].revents)
|
||||
/* Parent is asking us to quit. */
|
||||
break;
|
||||
|
||||
if (fds[1].revents) {
|
||||
/* Accept a new connection. */
|
||||
assert(fds[1].revents & POLLIN);
|
||||
AutoCloseFD fdClient = accept(fdServer.get(), nullptr, nullptr);
|
||||
if (!fdClient) continue;
|
||||
|
||||
/* Process the connection in a separate thread. */
|
||||
auto fdClient_ = fdClient.get();
|
||||
std::thread clientThread([&, fdClient = std::move(fdClient)]() {
|
||||
Finally cleanup([&]() {
|
||||
connections.lock()->erase(fdClient.get());
|
||||
});
|
||||
|
||||
while (true) {
|
||||
try {
|
||||
auto path = readLine(fdClient.get());
|
||||
auto storePath = maybeParseStorePath(path);
|
||||
if (storePath) {
|
||||
debug("got new GC root '%s'", path);
|
||||
auto hashPart = std::string(storePath->hashPart());
|
||||
auto shared(state.shared.lock());
|
||||
shared->tempRoots.insert(hashPart);
|
||||
/* If this path is currently being
|
||||
deleted, then we have to wait until
|
||||
deletion is finished to ensure that
|
||||
the client doesn't start
|
||||
re-creating it before we're
|
||||
done. FIXME: ideally we would use a
|
||||
FD for this so we don't block the
|
||||
poll loop. */
|
||||
while (shared->pending == hashPart) {
|
||||
debug("synchronising with deletion of path '%s'", path);
|
||||
shared.wait(state.wakeup);
|
||||
}
|
||||
} else
|
||||
printError("received garbage instead of a root from client");
|
||||
writeFull(fdClient.get(), "1", false);
|
||||
} catch (Error &) { break; }
|
||||
}
|
||||
}
|
||||
else {
|
||||
/* Receive data from a client. */
|
||||
auto fdClient = fdClients.find(fd.fd);
|
||||
assert(fdClient != fdClients.end());
|
||||
if (fd.revents & POLLIN) {
|
||||
char buf[16384];
|
||||
auto n = read(fd.fd, buf, sizeof(buf));
|
||||
if (n > 0) {
|
||||
fdClient->second.second.append(buf, n);
|
||||
/* Split the input into lines. */
|
||||
while (true) {
|
||||
auto p = fdClient->second.second.find('\n');
|
||||
if (p == std::string::npos) break;
|
||||
/* We got a full line. Send ack back
|
||||
to the client. */
|
||||
auto path = fdClient->second.second.substr(0, p);
|
||||
fdClient->second.second = fdClient->second.second.substr(p + 1);
|
||||
auto storePath = maybeParseStorePath(path);
|
||||
if (storePath) {
|
||||
debug("got new GC root '%s'", path);
|
||||
auto hashPart = std::string(storePath->hashPart());
|
||||
auto shared(state.shared.lock());
|
||||
shared->tempRoots.insert(hashPart);
|
||||
/* If this path is currently being
|
||||
deleted, then we have to wait
|
||||
until deletion is finished to
|
||||
ensure that the client doesn't
|
||||
start re-creating it before
|
||||
we're done. FIXME: ideally we
|
||||
would use a FD for this so we
|
||||
don't block the poll loop. */
|
||||
while (shared->pending == hashPart) {
|
||||
debug("synchronising with deletion of path '%s'", path);
|
||||
shared.wait(state.wakeup);
|
||||
}
|
||||
} else
|
||||
printError("received garbage instead of a root from client");
|
||||
// This could block, but meh.
|
||||
try {
|
||||
writeFull(fd.fd, "1", false);
|
||||
} catch (SysError &) { }
|
||||
}
|
||||
} else if (n == 0)
|
||||
fdClients.erase(fdClient);
|
||||
} else
|
||||
fdClients.erase(fdClient);
|
||||
}
|
||||
});
|
||||
|
||||
connections.lock()->insert({fdClient_, std::move(clientThread)});
|
||||
}
|
||||
}
|
||||
|
||||
debug("GC roots server shut down");
|
||||
});
|
||||
|
||||
Finally stopServer([&]() {
|
||||
|
|
|
|||
|
|
@ -511,6 +511,18 @@ std::optional<typename T::mapped_type> get(const T & map, const typename T::key_
|
|||
}
|
||||
|
||||
|
||||
/* Remove and return the first item from a container. */
|
||||
template <class T>
|
||||
std::optional<typename T::value_type> remove_begin(T & c)
|
||||
{
|
||||
auto i = c.begin();
|
||||
if (i == c.end()) return {};
|
||||
auto v = std::move(*i);
|
||||
c.erase(i);
|
||||
return v;
|
||||
}
|
||||
|
||||
|
||||
template<typename T>
|
||||
class Callback;
|
||||
|
||||
|
|
|
|||
Loading…
Reference in a new issue