--- /dev/null
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2015 Red Hat
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation. See file COPYING.
+ *
+ */
+
+#include "common/debug.h"
+#include "mds/mdstypes.h"
+#include "mds/CInode.h"
+#include "mds/MDCache.h"
+
+#include "PurgeQueue.h"
+
+
+#define dout_context cct
+#define dout_subsys ceph_subsys_mds
+#undef dout_prefix
+#define dout_prefix _prefix(_dout, rank) << __func__ << ": "
+static ostream& _prefix(std::ostream *_dout, mds_rank_t rank) {
+ return *_dout << "mds." << rank << ".purge_queue ";
+}
+
+void PurgeItem::encode(bufferlist &bl) const
+{
+ ENCODE_START(1, 1, bl);
+ ::encode((uint8_t)action, bl);
+ ::encode(ino, bl);
+ ::encode(size, bl);
+ ::encode(layout, bl, CEPH_FEATURE_FS_FILE_LAYOUT_V2);
+ ::encode(old_pools, bl);
+ ::encode(snapc, bl);
+ ::encode(fragtree, bl);
+ ENCODE_FINISH(bl);
+}
+
+void PurgeItem::decode(bufferlist::iterator &p)
+{
+ DECODE_START(1, p);
+ ::decode((uint8_t&)action, p);
+ ::decode(ino, p);
+ ::decode(size, p);
+ ::decode(layout, p);
+ ::decode(old_pools, p);
+ ::decode(snapc, p);
+ ::decode(fragtree, p);
+ DECODE_FINISH(p);
+}
+
+// TODO: if Objecter has any slow requests, take that as a hint and
+// slow down our rate of purging (keep accepting pushes though)
+PurgeQueue::PurgeQueue(
+ CephContext *cct_,
+ mds_rank_t rank_,
+ const int64_t metadata_pool_,
+ Objecter *objecter_,
+ Context *on_error_)
+ :
+ cct(cct_),
+ rank(rank_),
+ lock("PurgeQueue"),
+ metadata_pool(metadata_pool_),
+ finisher(cct, "PurgeQueue", "PQ_Finisher"),
+ timer(cct, lock),
+ filer(objecter_, &finisher),
+ objecter(objecter_),
+ journaler("pq", MDS_INO_PURGE_QUEUE + rank, metadata_pool,
+ CEPH_FS_ONDISK_MAGIC, objecter_, nullptr, 0,
+ &finisher),
+ on_error(on_error_),
+ ops_in_flight(0),
+ max_purge_ops(0),
+ drain_initial(0),
+ draining(false),
+ delayed_flush(nullptr),
+ recovered(false)
+{
+ assert(cct != nullptr);
+ assert(on_error != nullptr);
+ assert(objecter != nullptr);
+ journaler.set_write_error_handler(on_error);
+}
+
+PurgeQueue::~PurgeQueue()
+{
+ if (logger) {
+ g_ceph_context->get_perfcounters_collection()->remove(logger.get());
+ }
+}
+
+void PurgeQueue::create_logger()
+{
+ PerfCountersBuilder pcb(g_ceph_context,
+ "purge_queue", l_pq_first, l_pq_last);
+ pcb.add_u64(l_pq_executing_ops, "pq_executing_ops", "Purge queue ops in flight");
+ pcb.add_u64(l_pq_executing, "pq_executing", "Purge queue tasks in flight");
+ pcb.add_u64_counter(l_pq_executed, "pq_executed", "Purge queue tasks executed", "purg",
+ PerfCountersBuilder::PRIO_INTERESTING);
+
+ logger.reset(pcb.create_perf_counters());
+ g_ceph_context->get_perfcounters_collection()->add(logger.get());
+}
+
+void PurgeQueue::init()
+{
+ Mutex::Locker l(lock);
+
+ assert(logger != nullptr);
+
+ finisher.start();
+ timer.init();
+}
+
+void PurgeQueue::activate()
+{
+ Mutex::Locker l(lock);
+ if (journaler.get_read_pos() == journaler.get_write_pos())
+ return;
+
+ if (in_flight.empty()) {
+ dout(4) << "start work (by drain)" << dendl;
+ finisher.queue(new FunctionContext([this](int r) {
+ Mutex::Locker l(lock);
+ _consume();
+ }));
+ }
+}
+
+void PurgeQueue::shutdown()
+{
+ Mutex::Locker l(lock);
+
+ journaler.shutdown();
+ timer.shutdown();
+ finisher.stop();
+}
+
+void PurgeQueue::open(Context *completion)
+{
+ dout(4) << "opening" << dendl;
+
+ Mutex::Locker l(lock);
+
+ if (completion)
+ waiting_for_recovery.push_back(completion);
+
+ journaler.recover(new FunctionContext([this](int r){
+ if (r == -ENOENT) {
+ dout(1) << "Purge Queue not found, assuming this is an upgrade and "
+ "creating it." << dendl;
+ create(NULL);
+ } else if (r == 0) {
+ Mutex::Locker l(lock);
+ dout(4) << "open complete" << dendl;
+
+ // Journaler only guarantees entries before head write_pos have been
+ // fully flushed. Before appending new entries, we need to find and
+ // drop any partial written entry.
+ if (journaler.last_committed.write_pos < journaler.get_write_pos()) {
+ dout(4) << "recovering write_pos" << dendl;
+ journaler.set_read_pos(journaler.last_committed.write_pos);
+ _recover();
+ return;
+ }
+
+ journaler.set_writeable();
+ recovered = true;
+ finish_contexts(g_ceph_context, waiting_for_recovery);
+ } else {
+ derr << "Error " << r << " loading Journaler" << dendl;
+ on_error->complete(r);
+ }
+ }));
+}
+
+void PurgeQueue::wait_for_recovery(Context* c)
+{
+ Mutex::Locker l(lock);
+ if (recovered)
+ c->complete(0);
+ else
+ waiting_for_recovery.push_back(c);
+}
+
+void PurgeQueue::_recover()
+{
+ assert(lock.is_locked_by_me());
+
+ // Journaler::is_readable() adjusts write_pos if partial entry is encountered
+ while (1) {
+ if (!journaler.is_readable() &&
+ !journaler.get_error() &&
+ journaler.get_read_pos() < journaler.get_write_pos()) {
+ journaler.wait_for_readable(new FunctionContext([this](int r) {
+ Mutex::Locker l(lock);
+ _recover();
+ }));
+ return;
+ }
+
+ if (journaler.get_error()) {
+ int r = journaler.get_error();
+ derr << "Error " << r << " recovering write_pos" << dendl;
+ on_error->complete(r);
+ return;
+ }
+
+ if (journaler.get_read_pos() == journaler.get_write_pos()) {
+ dout(4) << "write_pos recovered" << dendl;
+ // restore original read_pos
+ journaler.set_read_pos(journaler.last_committed.expire_pos);
+ journaler.set_writeable();
+ recovered = true;
+ finish_contexts(g_ceph_context, waiting_for_recovery);
+ return;
+ }
+
+ bufferlist bl;
+ bool readable = journaler.try_read_entry(bl);
+ assert(readable); // we checked earlier
+ }
+}
+
+void PurgeQueue::create(Context *fin)
+{
+ dout(4) << "creating" << dendl;
+ Mutex::Locker l(lock);
+
+ if (fin)
+ waiting_for_recovery.push_back(fin);
+
+ file_layout_t layout = file_layout_t::get_default();
+ layout.pool_id = metadata_pool;
+ journaler.set_writeable();
+ journaler.create(&layout, JOURNAL_FORMAT_RESILIENT);
+ journaler.write_head(new FunctionContext([this](int r) {
+ Mutex::Locker l(lock);
+ recovered = true;
+ finish_contexts(g_ceph_context, waiting_for_recovery);
+ }));
+}
+
+/**
+ * The `completion` context will always be called back via a Finisher
+ */
+void PurgeQueue::push(const PurgeItem &pi, Context *completion)
+{
+ dout(4) << "pushing inode 0x" << std::hex << pi.ino << std::dec << dendl;
+ Mutex::Locker l(lock);
+
+ // Callers should have waited for open() before using us
+ assert(!journaler.is_readonly());
+
+ bufferlist bl;
+
+ ::encode(pi, bl);
+ journaler.append_entry(bl);
+ journaler.wait_for_flush(completion);
+
+ // Maybe go ahead and do something with it right away
+ bool could_consume = _consume();
+ if (!could_consume) {
+ // Usually, it is not necessary to explicitly flush here, because the reader
+ // will get flushes generated inside Journaler::is_readable. However,
+ // if we remain in a can_consume()==false state for a long period then
+ // we should flush in order to allow MDCache to drop its strays rather
+ // than having them wait for purgequeue to progress.
+ if (!delayed_flush) {
+ delayed_flush = new FunctionContext([this](int r){
+ delayed_flush = nullptr;
+ journaler.flush();
+ });
+
+ timer.add_event_after(
+ g_conf->mds_purge_queue_busy_flush_period,
+ delayed_flush);
+ }
+ }
+}
+
+uint32_t PurgeQueue::_calculate_ops(const PurgeItem &item) const
+{
+ uint32_t ops_required = 0;
+ if (item.action == PurgeItem::PURGE_DIR) {
+ // Directory, count dirfrags to be deleted
+ std::list<frag_t> ls;
+ if (!item.fragtree.is_leaf(frag_t())) {
+ item.fragtree.get_leaves(ls);
+ }
+ // One for the root, plus any leaves
+ ops_required = 1 + ls.size();
+ } else {
+ // File, work out concurrent Filer::purge deletes
+ const uint64_t num = (item.size > 0) ?
+ Striper::get_num_objects(item.layout, item.size) : 1;
+
+ ops_required = MIN(num, g_conf->filer_max_purge_ops);
+
+ // Account for removing (or zeroing) backtrace
+ ops_required += 1;
+
+ // Account for deletions for old pools
+ if (item.action != PurgeItem::TRUNCATE_FILE) {
+ ops_required += item.old_pools.size();
+ }
+ }
+
+ return ops_required;
+}
+
+bool PurgeQueue::can_consume()
+{
+ dout(20) << ops_in_flight << "/" << max_purge_ops << " ops, "
+ << in_flight.size() << "/" << g_conf->mds_max_purge_files
+ << " files" << dendl;
+
+ if (in_flight.size() == 0 && cct->_conf->mds_max_purge_files > 0) {
+ // Always permit consumption if nothing is in flight, so that the ops
+ // limit can never be so low as to forbid all progress (unless
+ // administrator has deliberately paused purging by setting max
+ // purge files to zero).
+ return true;
+ }
+
+ if (ops_in_flight >= max_purge_ops) {
+ dout(20) << "Throttling on op limit " << ops_in_flight << "/"
+ << max_purge_ops << dendl;
+ return false;
+ }
+
+ if (in_flight.size() >= cct->_conf->mds_max_purge_files) {
+ dout(20) << "Throttling on item limit " << in_flight.size()
+ << "/" << cct->_conf->mds_max_purge_files << dendl;
+ return false;
+ } else {
+ return true;
+ }
+}
+
+bool PurgeQueue::_consume()
+{
+ assert(lock.is_locked_by_me());
+
+ bool could_consume = false;
+ while(can_consume()) {
+ could_consume = true;
+
+ if (delayed_flush) {
+ // We are now going to read from the journal, so any proactive
+ // flush is no longer necessary. This is not functionally necessary
+ // but it can avoid generating extra fragmented flush IOs.
+ timer.cancel_event(delayed_flush);
+ delayed_flush = nullptr;
+ }
+
+ if (!journaler.is_readable()) {
+ dout(10) << " not readable right now" << dendl;
+ // Because we are the writer and the reader of the journal
+ // via the same Journaler instance, we never need to reread_head
+ if (!journaler.have_waiter()) {
+ journaler.wait_for_readable(new FunctionContext([this](int r) {
+ Mutex::Locker l(lock);
+ if (r == 0) {
+ _consume();
+ }
+ }));
+ }
+
+ return could_consume;
+ }
+
+ // The journaler is readable: consume an entry
+ bufferlist bl;
+ bool readable = journaler.try_read_entry(bl);
+ assert(readable); // we checked earlier
+
+ dout(20) << " decoding entry" << dendl;
+ PurgeItem item;
+ bufferlist::iterator q = bl.begin();
+ try {
+ ::decode(item, q);
+ } catch (const buffer::error &err) {
+ derr << "Decode error at read_pos=0x" << std::hex
+ << journaler.get_read_pos() << dendl;
+ on_error->complete(0);
+ }
+ dout(20) << " executing item (0x" << std::hex << item.ino
+ << std::dec << ")" << dendl;
+ _execute_item(item, journaler.get_read_pos());
+ }
+
+ dout(10) << " cannot consume right now" << dendl;
+
+ return could_consume;
+}
+
+void PurgeQueue::_execute_item(
+ const PurgeItem &item,
+ uint64_t expire_to)
+{
+ assert(lock.is_locked_by_me());
+
+ in_flight[expire_to] = item;
+ logger->set(l_pq_executing, in_flight.size());
+ ops_in_flight += _calculate_ops(item);
+ logger->set(l_pq_executing_ops, ops_in_flight);
+
+ SnapContext nullsnapc;
+
+ C_GatherBuilder gather(cct);
+ if (item.action == PurgeItem::PURGE_FILE) {
+ if (item.size > 0) {
+ uint64_t num = Striper::get_num_objects(item.layout, item.size);
+ dout(10) << " 0~" << item.size << " objects 0~" << num
+ << " snapc " << item.snapc << " on " << item.ino << dendl;
+ filer.purge_range(item.ino, &item.layout, item.snapc,
+ 0, num, ceph::real_clock::now(), 0,
+ gather.new_sub());
+ }
+
+ // remove the backtrace object if it was not purged
+ object_t oid = CInode::get_object_name(item.ino, frag_t(), "");
+ if (!gather.has_subs() || !item.layout.pool_ns.empty()) {
+ object_locator_t oloc(item.layout.pool_id);
+ dout(10) << " remove backtrace object " << oid
+ << " pool " << oloc.pool << " snapc " << item.snapc << dendl;
+ objecter->remove(oid, oloc, item.snapc,
+ ceph::real_clock::now(), 0,
+ gather.new_sub());
+ }
+
+ // remove old backtrace objects
+ for (const auto &p : item.old_pools) {
+ object_locator_t oloc(p);
+ dout(10) << " remove backtrace object " << oid
+ << " old pool " << p << " snapc " << item.snapc << dendl;
+ objecter->remove(oid, oloc, item.snapc,
+ ceph::real_clock::now(), 0,
+ gather.new_sub());
+ }
+ } else if (item.action == PurgeItem::PURGE_DIR) {
+ object_locator_t oloc(metadata_pool);
+ std::list<frag_t> frags;
+ if (!item.fragtree.is_leaf(frag_t()))
+ item.fragtree.get_leaves(frags);
+ frags.push_back(frag_t());
+ for (const auto &frag : frags) {
+ object_t oid = CInode::get_object_name(item.ino, frag, "");
+ dout(10) << " remove dirfrag " << oid << dendl;
+ objecter->remove(oid, oloc, nullsnapc,
+ ceph::real_clock::now(),
+ 0, gather.new_sub());
+ }
+ } else if (item.action == PurgeItem::TRUNCATE_FILE) {
+ const uint64_t num = Striper::get_num_objects(item.layout, item.size);
+ dout(10) << " 0~" << item.size << " objects 0~" << num
+ << " snapc " << item.snapc << " on " << item.ino << dendl;
+
+ // keep backtrace object
+ if (num > 1) {
+ filer.purge_range(item.ino, &item.layout, item.snapc,
+ 1, num - 1, ceph::real_clock::now(),
+ 0, gather.new_sub());
+ }
+ filer.zero(item.ino, &item.layout, item.snapc,
+ 0, item.layout.object_size,
+ ceph::real_clock::now(),
+ 0, true, gather.new_sub());
+ } else {
+ derr << "Invalid item (action=" << item.action << ") in purge queue, "
+ "dropping it" << dendl;
+ in_flight.erase(expire_to);
+ logger->set(l_pq_executing, in_flight.size());
+ return;
+ }
+ assert(gather.has_subs());
+
+ gather.set_finisher(new C_OnFinisher(
+ new FunctionContext([this, expire_to](int r){
+ Mutex::Locker l(lock);
+ _execute_item_complete(expire_to);
+
+ _consume();
+
+ // Have we gone idle? If so, do an extra write_head now instead of
+ // waiting for next flush after journaler_write_head_interval.
+ // Also do this periodically even if not idle, so that the persisted
+ // expire_pos doesn't fall too far behind our progress when consuming
+ // a very long queue.
+ if (in_flight.empty() || journaler.write_head_needed()) {
+ journaler.write_head(new FunctionContext([this](int r){
+ journaler.trim();
+ }));
+ }
+ }), &finisher));
+
+ gather.activate();
+}
+
+void PurgeQueue::_execute_item_complete(
+ uint64_t expire_to)
+{
+ assert(lock.is_locked_by_me());
+ dout(10) << "complete at 0x" << std::hex << expire_to << std::dec << dendl;
+ assert(in_flight.count(expire_to) == 1);
+
+ auto iter = in_flight.find(expire_to);
+ assert(iter != in_flight.end());
+ if (iter == in_flight.begin()) {
+ // This was the lowest journal position in flight, so we can now
+ // safely expire the journal up to here.
+ dout(10) << "expiring to 0x" << std::hex << expire_to << std::dec << dendl;
+ journaler.set_expire_pos(expire_to);
+ } else {
+ // This is completely fine, we're not supposed to purge files in
+ // order when doing them in parallel.
+ dout(10) << "non-sequential completion, not expiring anything" << dendl;
+ }
+
+ ops_in_flight -= _calculate_ops(iter->second);
+ logger->set(l_pq_executing_ops, ops_in_flight);
+
+ dout(10) << "completed item for ino 0x" << std::hex << iter->second.ino
+ << std::dec << dendl;
+
+ in_flight.erase(iter);
+ logger->set(l_pq_executing, in_flight.size());
+ dout(10) << "in_flight.size() now " << in_flight.size() << dendl;
+
+ logger->inc(l_pq_executed);
+}
+
+void PurgeQueue::update_op_limit(const MDSMap &mds_map)
+{
+ Mutex::Locker l(lock);
+
+ uint64_t pg_count = 0;
+ objecter->with_osdmap([&](const OSDMap& o) {
+ // Number of PGs across all data pools
+ const std::vector<int64_t> &data_pools = mds_map.get_data_pools();
+ for (const auto dp : data_pools) {
+ if (o.get_pg_pool(dp) == NULL) {
+ // It is possible that we have an older OSDMap than MDSMap,
+ // because we don't start watching every OSDMap until after
+ // MDSRank is initialized
+ dout(4) << " data pool " << dp << " not found in OSDMap" << dendl;
+ continue;
+ }
+ pg_count += o.get_pg_num(dp);
+ }
+ });
+
+ // Work out a limit based on n_pgs / n_mdss, multiplied by the user's
+ // preference for how many ops per PG
+ max_purge_ops = uint64_t(((double)pg_count / (double)mds_map.get_max_mds()) *
+ cct->_conf->mds_max_purge_ops_per_pg);
+
+ // User may also specify a hard limit, apply this if so.
+ if (cct->_conf->mds_max_purge_ops) {
+ max_purge_ops = MIN(max_purge_ops, cct->_conf->mds_max_purge_ops);
+ }
+}
+
+void PurgeQueue::handle_conf_change(const struct md_config_t *conf,
+ const std::set <std::string> &changed,
+ const MDSMap &mds_map)
+{
+ if (changed.count("mds_max_purge_ops")
+ || changed.count("mds_max_purge_ops_per_pg")) {
+ update_op_limit(mds_map);
+ } else if (changed.count("mds_max_purge_files")) {
+ Mutex::Locker l(lock);
+
+ if (in_flight.empty()) {
+ // We might have gone from zero to a finite limit, so
+ // might need to kick off consume.
+ dout(4) << "maybe start work again (max_purge_files="
+ << conf->mds_max_purge_files << dendl;
+ finisher.queue(new FunctionContext([this](int r){
+ Mutex::Locker l(lock);
+ _consume();
+ }));
+ }
+ }
+}
+
+bool PurgeQueue::drain(
+ uint64_t *progress,
+ uint64_t *progress_total,
+ size_t *in_flight_count
+ )
+{
+ assert(progress != nullptr);
+ assert(progress_total != nullptr);
+ assert(in_flight_count != nullptr);
+
+ const bool done = in_flight.empty() && (
+ journaler.get_read_pos() == journaler.get_write_pos());
+ if (done) {
+ return true;
+ }
+
+ const uint64_t bytes_remaining = journaler.get_write_pos()
+ - journaler.get_read_pos();
+
+ if (!draining) {
+ // Start of draining: remember how much there was outstanding at
+ // this point so that we can give a progress percentage later
+ draining = true;
+
+ // Life the op throttle as this daemon now has nothing to do but
+ // drain the purge queue, so do it as fast as we can.
+ max_purge_ops = 0xffff;
+ }
+
+ drain_initial = max(bytes_remaining, drain_initial);
+
+ *progress = drain_initial - bytes_remaining;
+ *progress_total = drain_initial;
+ *in_flight_count = in_flight.size();
+
+ return false;
+}
+
Code Review / stor4nfv.git / blobdiff