1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
2 // vim: ts=8 sw=2 smarttab
4 * Ceph - scalable distributed file system
6 * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
8 * This is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License version 2.1, as published by the Free Software
11 * Foundation. See file COPYING.
15 #include "include/compat.h"
18 #include "MDBalancer.h"
20 #include "mon/MonClient.h"
28 #include "include/Context.h"
29 #include "msg/Messenger.h"
30 #include "messages/MHeartbeat.h"
39 #include "common/config.h"
40 #include "common/errno.h"
42 #define dout_context g_ceph_context
43 #define dout_subsys ceph_subsys_mds
45 #define dout_prefix *_dout << "mds." << mds->get_nodeid() << ".bal "
49 auto subsys = ceph_subsys_mds;\
50 if ((dout_context)->_conf->subsys.should_gather(ceph_subsys_mds_balancer, lvl)) {\
51 subsys = ceph_subsys_mds_balancer;\
53 dout_impl(dout_context, subsys, lvl) dout_prefix
55 #define dendl dendl_impl; } while (0)
58 #define MIN_LOAD 50 // ??
59 #define MIN_REEXPORT 5 // will automatically reexport
60 #define MIN_OFFLOAD 10 // point at which i stop trying, close enough
63 /* This function DOES put the passed message before returning */
64 int MDBalancer::proc_message(Message
*m
)
66 switch (m
->get_type()) {
68 case MSG_MDS_HEARTBEAT
:
69 handle_heartbeat(static_cast<MHeartbeat
*>(m
));
73 dout(0) << " balancer unknown message " << m
->get_type() << dendl
;
74 assert(0 == "balancer unknown message");
80 void MDBalancer::handle_export_pins(void)
82 auto &q
= mds
->mdcache
->export_pin_queue
;
84 dout(20) << "export_pin_queue size=" << q
.size() << dendl
;
85 while (it
!= q
.end()) {
89 mds_rank_t export_pin
= in
->get_export_pin(false);
93 in
->get_dirfrags(dfls
);
94 for (auto dir
: dfls
) {
98 if (export_pin
== MDS_RANK_NONE
) {
99 if (dir
->state_test(CDir::STATE_AUXSUBTREE
)) {
100 if (dir
->is_frozen() || dir
->is_freezing()) {
105 dout(10) << " clear auxsubtree on " << *dir
<< dendl
;
106 dir
->state_clear(CDir::STATE_AUXSUBTREE
);
107 mds
->mdcache
->try_subtree_merge(dir
);
109 } else if (export_pin
== mds
->get_nodeid()) {
110 if (dir
->state_test(CDir::STATE_CREATING
) ||
111 dir
->is_frozen() || dir
->is_freezing()) {
116 if (!dir
->is_subtree_root()) {
117 dir
->state_set(CDir::STATE_AUXSUBTREE
);
118 mds
->mdcache
->adjust_subtree_auth(dir
, mds
->get_nodeid());
119 dout(10) << " create aux subtree on " << *dir
<< dendl
;
120 } else if (!dir
->state_test(CDir::STATE_AUXSUBTREE
)) {
121 dout(10) << " set auxsubtree bit on " << *dir
<< dendl
;
122 dir
->state_set(CDir::STATE_AUXSUBTREE
);
125 mds
->mdcache
->migrator
->export_dir(dir
, export_pin
);
131 in
->state_clear(CInode::STATE_QUEUEDEXPORTPIN
);
136 set
<CDir
*> authsubs
;
137 mds
->mdcache
->get_auth_subtrees(authsubs
);
138 for (auto &cd
: authsubs
) {
139 mds_rank_t export_pin
= cd
->inode
->get_export_pin();
140 dout(10) << "auth tree " << *cd
<< " export_pin=" << export_pin
<< dendl
;
141 if (export_pin
>= 0 && export_pin
!= mds
->get_nodeid()) {
142 dout(10) << "exporting auth subtree " << *cd
->inode
<< " to " << export_pin
<< dendl
;
143 mds
->mdcache
->migrator
->export_dir(cd
, export_pin
);
148 void MDBalancer::tick()
150 static int num_bal_times
= g_conf
->mds_bal_max
;
151 static utime_t first
= ceph_clock_now();
152 utime_t now
= ceph_clock_now();
153 utime_t elapsed
= now
;
156 if (g_conf
->mds_bal_export_pin
) {
157 handle_export_pins();
161 if ((double)now
- (double)last_sample
> g_conf
->mds_bal_sample_interval
) {
162 dout(15) << "tick last_sample now " << now
<< dendl
;
167 if (last_heartbeat
== utime_t())
168 last_heartbeat
= now
;
169 if (mds
->get_nodeid() == 0 &&
170 g_conf
->mds_bal_interval
> 0 &&
172 (g_conf
->mds_bal_max_until
>= 0 &&
173 elapsed
.sec() > g_conf
->mds_bal_max_until
)) &&
175 now
.sec() - last_heartbeat
.sec() >= g_conf
->mds_bal_interval
) {
176 last_heartbeat
= now
;
185 class C_Bal_SendHeartbeat
: public MDSInternalContext
{
187 explicit C_Bal_SendHeartbeat(MDSRank
*mds_
) : MDSInternalContext(mds_
) { }
188 void finish(int f
) override
{
189 mds
->balancer
->send_heartbeat();
194 double mds_load_t::mds_load()
196 switch(g_conf
->mds_bal_mode
) {
199 .8 * auth
.meta_load() +
200 .2 * all
.meta_load() +
205 return req_rate
+ 10.0*queue_len
;
215 mds_load_t
MDBalancer::get_load(utime_t now
)
217 mds_load_t
load(now
);
219 if (mds
->mdcache
->get_root()) {
221 mds
->mdcache
->get_root()->get_dirfrags(ls
);
222 for (list
<CDir
*>::iterator p
= ls
.begin();
225 load
.auth
.add(now
, mds
->mdcache
->decayrate
, (*p
)->pop_auth_subtree_nested
);
226 load
.all
.add(now
, mds
->mdcache
->decayrate
, (*p
)->pop_nested
);
229 dout(20) << "get_load no root, no load" << dendl
;
232 load
.req_rate
= mds
->get_req_rate();
233 load
.queue_len
= messenger
->get_dispatch_queue_len();
235 ifstream
cpu(PROCPREFIX
"/proc/loadavg");
237 cpu
>> load
.cpu_load_avg
;
239 dout(0) << "input file " PROCPREFIX
"'/proc/loadavg' not found" << dendl
;
241 dout(15) << "get_load " << load
<< dendl
;
246 * Read synchronously from RADOS using a timeout. We cannot do daemon-local
247 * fallbacks (i.e. kick off async read when we are processing the map and
248 * check status when we get here) with the way the mds is structured.
250 int MDBalancer::localize_balancer()
252 /* reset everything */
259 /* we assume that balancer is in the metadata pool */
260 object_t oid
= object_t(mds
->mdsmap
->get_balancer());
261 object_locator_t
oloc(mds
->mdsmap
->get_metadata_pool());
262 ceph_tid_t tid
= mds
->objecter
->read(oid
, oloc
, 0, 0, CEPH_NOSNAP
, &lua_src
, 0,
263 new C_SafeCond(&lock
, &cond
, &ack
, &r
));
264 dout(15) << "launched non-blocking read tid=" << tid
265 << " oid=" << oid
<< " oloc=" << oloc
<< dendl
;
267 /* timeout: if we waste half our time waiting for RADOS, then abort! */
268 double t
= ceph_clock_now() + g_conf
->mds_bal_interval
/2;
270 timeout
.set_from_double(t
);
272 int ret_t
= cond
.WaitUntil(lock
, timeout
);
275 /* success: store the balancer in memory and set the version. */
277 if (ret_t
== ETIMEDOUT
) {
278 mds
->objecter
->op_cancel(tid
, -ECANCELED
);
281 bal_code
.assign(lua_src
.to_str());
282 bal_version
.assign(oid
.name
);
283 dout(0) << "localized balancer, bal_code=" << bal_code
<< dendl
;
288 void MDBalancer::send_heartbeat()
290 utime_t now
= ceph_clock_now();
292 if (mds
->is_cluster_degraded()) {
293 dout(10) << "send_heartbeat degraded" << dendl
;
297 if (!mds
->mdcache
->is_open()) {
298 dout(5) << "not open" << dendl
;
299 mds
->mdcache
->wait_for_open(new C_Bal_SendHeartbeat(mds
));
304 if (mds
->get_nodeid() == 0)
308 mds_load_t load
= get_load(now
);
309 map
<mds_rank_t
, mds_load_t
>::value_type
val(mds
->get_nodeid(), load
);
310 mds_load
.insert(val
);
312 // import_map -- how much do i import from whom
313 map
<mds_rank_t
, float> import_map
;
315 mds
->mdcache
->get_auth_subtrees(authsubs
);
316 for (set
<CDir
*>::iterator it
= authsubs
.begin();
317 it
!= authsubs
.end();
320 mds_rank_t from
= im
->inode
->authority().first
;
321 if (from
== mds
->get_nodeid()) continue;
322 if (im
->get_inode()->is_stray()) continue;
323 import_map
[from
] += im
->pop_auth_subtree
.meta_load(now
, mds
->mdcache
->decayrate
);
325 mds_import_map
[ mds
->get_nodeid() ] = import_map
;
328 dout(5) << "mds." << mds
->get_nodeid() << " epoch " << beat_epoch
<< " load " << load
<< dendl
;
329 for (map
<mds_rank_t
, float>::iterator it
= import_map
.begin();
330 it
!= import_map
.end();
332 dout(5) << " import_map from " << it
->first
<< " -> " << it
->second
<< dendl
;
337 mds
->get_mds_map()->get_up_mds_set(up
);
338 for (set
<mds_rank_t
>::iterator p
= up
.begin(); p
!= up
.end(); ++p
) {
339 if (*p
== mds
->get_nodeid())
341 MHeartbeat
*hb
= new MHeartbeat(load
, beat_epoch
);
342 hb
->get_import_map() = import_map
;
343 messenger
->send_message(hb
,
344 mds
->mdsmap
->get_inst(*p
));
348 /* This function DOES put the passed message before returning */
349 void MDBalancer::handle_heartbeat(MHeartbeat
*m
)
351 typedef map
<mds_rank_t
, mds_load_t
> mds_load_map_t
;
353 mds_rank_t who
= mds_rank_t(m
->get_source().num());
354 dout(25) << "=== got heartbeat " << m
->get_beat() << " from " << m
->get_source().num() << " " << m
->get_load() << dendl
;
356 if (!mds
->is_active())
359 if (!mds
->mdcache
->is_open()) {
360 dout(10) << "opening root on handle_heartbeat" << dendl
;
361 mds
->mdcache
->wait_for_open(new C_MDS_RetryMessage(mds
, m
));
365 if (mds
->is_cluster_degraded()) {
366 dout(10) << " degraded, ignoring" << dendl
;
371 dout(20) << " from mds0, new epoch" << dendl
;
372 beat_epoch
= m
->get_beat();
375 mds
->mdcache
->show_subtrees();
380 mds_load_map_t::value_type
val(who
, m
->get_load());
381 pair
< mds_load_map_t::iterator
, bool > rval (mds_load
.insert(val
));
383 rval
.first
->second
= val
.second
;
386 mds_import_map
[ who
] = m
->get_import_map();
388 //dout(0) << " load is " << load << " have " << mds_load.size() << dendl;
391 unsigned cluster_size
= mds
->get_mds_map()->get_num_in_mds();
392 if (mds_load
.size() == cluster_size
) {
394 //export_empties(); // no!
396 /* avoid spamming ceph -w if user does not turn mantle on */
397 if (mds
->mdsmap
->get_balancer() != "") {
398 int r
= mantle_prep_rebalance();
400 mds
->clog
->warn() << "using old balancer; mantle failed for "
401 << "balancer=" << mds
->mdsmap
->get_balancer()
402 << " : " << cpp_strerror(r
);
404 prep_rebalance(m
->get_beat());
414 void MDBalancer::export_empties()
416 dout(5) << "export_empties checking for empty imports" << dendl
;
418 std::set
<CDir
*> subtrees
;
419 mds
->mdcache
->get_fullauth_subtrees(subtrees
);
420 for (auto &dir
: subtrees
) {
421 if (dir
->is_freezing() || dir
->is_frozen())
424 if (!dir
->inode
->is_base() &&
425 !dir
->inode
->is_stray() &&
426 dir
->get_num_head_items() == 0)
427 mds
->mdcache
->migrator
->export_empty_import(dir
);
433 double MDBalancer::try_match(balance_state_t
& state
, mds_rank_t ex
, double& maxex
,
434 mds_rank_t im
, double& maxim
)
436 if (maxex
<= 0 || maxim
<= 0) return 0.0;
438 double howmuch
= MIN(maxex
, maxim
);
439 if (howmuch
<= 0) return 0.0;
441 dout(5) << " - mds." << ex
<< " exports " << howmuch
<< " to mds." << im
<< dendl
;
443 if (ex
== mds
->get_nodeid())
444 state
.targets
[im
] += howmuch
;
446 state
.exported
[ex
] += howmuch
;
447 state
.imported
[im
] += howmuch
;
455 void MDBalancer::queue_split(const CDir
*dir
, bool fast
)
457 dout(10) << __func__
<< " enqueuing " << *dir
458 << " (fast=" << fast
<< ")" << dendl
;
460 assert(mds
->mdsmap
->allows_dirfrags());
461 const dirfrag_t frag
= dir
->dirfrag();
463 auto callback
= [this, frag
](int r
) {
464 if (split_pending
.erase(frag
) == 0) {
465 // Someone beat me to it. This can happen in the fast splitting
466 // path, because we spawn two contexts, one with mds->timer and
467 // one with mds->queue_waiter. The loser can safely just drop
472 CDir
*split_dir
= mds
->mdcache
->get_dirfrag(frag
);
474 dout(10) << "drop split on " << frag
<< " because not in cache" << dendl
;
477 if (!split_dir
->is_auth()) {
478 dout(10) << "drop split on " << frag
<< " because non-auth" << dendl
;
482 // Pass on to MDCache: note that the split might still not
483 // happen if the checks in MDCache::can_fragment fail.
484 dout(10) << __func__
<< " splitting " << *split_dir
<< dendl
;
485 mds
->mdcache
->split_dir(split_dir
, g_conf
->mds_bal_split_bits
);
489 if (split_pending
.count(frag
) == 0) {
490 split_pending
.insert(frag
);
495 // Do the split ASAP: enqueue it in the MDSRank waiters which are
496 // run at the end of dispatching the current request
497 mds
->queue_waiter(new MDSInternalContextWrapper(mds
,
498 new FunctionContext(callback
)));
500 // Set a timer to really do the split: we don't do it immediately
501 // so that bursts of ops on a directory have a chance to go through
502 // before we freeze it.
503 mds
->timer
.add_event_after(g_conf
->mds_bal_fragment_interval
,
504 new FunctionContext(callback
));
508 void MDBalancer::queue_merge(CDir
*dir
)
510 const auto frag
= dir
->dirfrag();
511 auto callback
= [this, frag
](int r
) {
512 assert(frag
.frag
!= frag_t());
514 // frag must be in this set because only one context is in flight
515 // for a given frag at a time (because merge_pending is checked before
516 // starting one), and this context is the only one that erases it.
517 merge_pending
.erase(frag
);
519 CDir
*dir
= mds
->mdcache
->get_dirfrag(frag
);
521 dout(10) << "drop merge on " << frag
<< " because not in cache" << dendl
;
524 assert(dir
->dirfrag() == frag
);
526 if(!dir
->is_auth()) {
527 dout(10) << "drop merge on " << *dir
<< " because lost auth" << dendl
;
531 dout(10) << "merging " << *dir
<< dendl
;
533 CInode
*diri
= dir
->get_inode();
535 frag_t fg
= dir
->get_frag();
536 while (fg
!= frag_t()) {
537 frag_t sibfg
= fg
.get_sibling();
539 bool complete
= diri
->get_dirfrags_under(sibfg
, sibs
);
541 dout(10) << " not all sibs under " << sibfg
<< " in cache (have " << sibs
<< ")" << dendl
;
545 for (list
<CDir
*>::iterator p
= sibs
.begin(); p
!= sibs
.end(); ++p
) {
547 if (!sib
->is_auth() || !sib
->should_merge()) {
553 dout(10) << " not all sibs under " << sibfg
<< " " << sibs
<< " should_merge" << dendl
;
556 dout(10) << " all sibs under " << sibfg
<< " " << sibs
<< " should merge" << dendl
;
560 if (fg
!= dir
->get_frag())
561 mds
->mdcache
->merge_dir(diri
, fg
);
564 if (merge_pending
.count(frag
) == 0) {
565 dout(20) << __func__
<< " enqueued dir " << *dir
<< dendl
;
566 merge_pending
.insert(frag
);
567 mds
->timer
.add_event_after(g_conf
->mds_bal_fragment_interval
,
568 new FunctionContext(callback
));
570 dout(20) << __func__
<< " dir already in queue " << *dir
<< dendl
;
574 void MDBalancer::prep_rebalance(int beat
)
576 balance_state_t state
;
578 if (g_conf
->mds_thrash_exports
) {
579 //we're going to randomly export to all the mds in the cluster
580 set
<mds_rank_t
> up_mds
;
581 mds
->get_mds_map()->get_up_mds_set(up_mds
);
582 for (const auto &rank
: up_mds
) {
583 state
.targets
[rank
] = 0.0;
586 int cluster_size
= mds
->get_mds_map()->get_num_in_mds();
587 mds_rank_t whoami
= mds
->get_nodeid();
588 rebalance_time
= ceph_clock_now();
590 dout(5) << " prep_rebalance: cluster loads are" << dendl
;
592 mds
->mdcache
->migrator
->clear_export_queue();
594 // rescale! turn my mds_load back into meta_load units
595 double load_fac
= 1.0;
596 map
<mds_rank_t
, mds_load_t
>::iterator m
= mds_load
.find(whoami
);
597 if ((m
!= mds_load
.end()) && (m
->second
.mds_load() > 0)) {
598 double metald
= m
->second
.auth
.meta_load(rebalance_time
, mds
->mdcache
->decayrate
);
599 double mdsld
= m
->second
.mds_load();
600 load_fac
= metald
/ mdsld
;
601 dout(7) << " load_fac is " << load_fac
602 << " <- " << m
->second
.auth
<< " " << metald
607 double total_load
= 0.0;
608 multimap
<double,mds_rank_t
> load_map
;
609 for (mds_rank_t i
=mds_rank_t(0); i
< mds_rank_t(cluster_size
); i
++) {
610 map
<mds_rank_t
, mds_load_t
>::value_type
val(i
, mds_load_t(ceph_clock_now()));
611 std::pair
< map
<mds_rank_t
, mds_load_t
>::iterator
, bool > r(mds_load
.insert(val
));
612 mds_load_t
&load(r
.first
->second
);
614 double l
= load
.mds_load() * load_fac
;
615 mds_meta_load
[i
] = l
;
618 dout(0) << " mds." << i
620 << " = " << load
.mds_load()
621 << " ~ " << l
<< dendl
;
623 if (whoami
== i
) my_load
= l
;
626 load_map
.insert(pair
<double,mds_rank_t
>( l
, i
));
630 target_load
= total_load
/ (double)cluster_size
;
631 dout(5) << "prep_rebalance: my load " << my_load
632 << " target " << target_load
633 << " total " << total_load
637 if (my_load
< target_load
* (1.0 + g_conf
->mds_bal_min_rebalance
)) {
638 dout(5) << " i am underloaded or barely overloaded, doing nothing." << dendl
;
639 last_epoch_under
= beat_epoch
;
640 mds
->mdcache
->show_subtrees();
644 // am i over long enough?
645 if (last_epoch_under
&& beat_epoch
- last_epoch_under
< 2) {
646 dout(5) << " i am overloaded, but only for " << (beat_epoch
- last_epoch_under
) << " epochs" << dendl
;
650 dout(5) << " i am sufficiently overloaded" << dendl
;
653 // first separate exporters and importers
654 multimap
<double,mds_rank_t
> importers
;
655 multimap
<double,mds_rank_t
> exporters
;
656 set
<mds_rank_t
> importer_set
;
657 set
<mds_rank_t
> exporter_set
;
659 for (multimap
<double,mds_rank_t
>::iterator it
= load_map
.begin();
660 it
!= load_map
.end();
662 if (it
->first
< target_load
) {
663 dout(15) << " mds." << it
->second
<< " is importer" << dendl
;
664 importers
.insert(pair
<double,mds_rank_t
>(it
->first
,it
->second
));
665 importer_set
.insert(it
->second
);
667 dout(15) << " mds." << it
->second
<< " is exporter" << dendl
;
668 exporters
.insert(pair
<double,mds_rank_t
>(it
->first
,it
->second
));
669 exporter_set
.insert(it
->second
);
674 // determine load transfer mapping
677 // analyze import_map; do any matches i can
679 dout(15) << " matching exporters to import sources" << dendl
;
681 // big -> small exporters
682 for (multimap
<double,mds_rank_t
>::reverse_iterator ex
= exporters
.rbegin();
683 ex
!= exporters
.rend();
685 double maxex
= get_maxex(state
, ex
->second
);
686 if (maxex
<= .001) continue;
688 // check importers. for now, just in arbitrary order (no intelligent matching).
689 for (map
<mds_rank_t
, float>::iterator im
= mds_import_map
[ex
->second
].begin();
690 im
!= mds_import_map
[ex
->second
].end();
692 double maxim
= get_maxim(state
, im
->first
);
693 if (maxim
<= .001) continue;
694 try_match(state
, ex
->second
, maxex
, im
->first
, maxim
);
695 if (maxex
<= .001) break;
702 dout(15) << " matching big exporters to big importers" << dendl
;
703 // big exporters to big importers
704 multimap
<double,mds_rank_t
>::reverse_iterator ex
= exporters
.rbegin();
705 multimap
<double,mds_rank_t
>::iterator im
= importers
.begin();
706 while (ex
!= exporters
.rend() &&
707 im
!= importers
.end()) {
708 double maxex
= get_maxex(state
, ex
->second
);
709 double maxim
= get_maxim(state
, im
->second
);
710 if (maxex
< .001 || maxim
< .001) break;
711 try_match(state
, ex
->second
, maxex
, im
->second
, maxim
);
712 if (maxex
<= .001) ++ex
;
713 if (maxim
<= .001) ++im
;
716 dout(15) << " matching small exporters to big importers" << dendl
;
717 // small exporters to big importers
718 multimap
<double,mds_rank_t
>::iterator ex
= exporters
.begin();
719 multimap
<double,mds_rank_t
>::iterator im
= importers
.begin();
720 while (ex
!= exporters
.end() &&
721 im
!= importers
.end()) {
722 double maxex
= get_maxex(state
, ex
->second
);
723 double maxim
= get_maxim(state
, im
->second
);
724 if (maxex
< .001 || maxim
< .001) break;
725 try_match(state
, ex
->second
, maxex
, im
->second
, maxim
);
726 if (maxex
<= .001) ++ex
;
727 if (maxim
<= .001) ++im
;
731 try_rebalance(state
);
734 int MDBalancer::mantle_prep_rebalance()
736 balance_state_t state
;
738 /* refresh balancer if it has changed */
739 if (bal_version
!= mds
->mdsmap
->get_balancer()) {
740 bal_version
.assign("");
741 int r
= localize_balancer();
744 /* only spam the cluster log from 1 mds on version changes */
745 if (mds
->get_nodeid() == 0)
746 mds
->clog
->info() << "mantle balancer version changed: " << bal_version
;
749 /* prepare for balancing */
750 int cluster_size
= mds
->get_mds_map()->get_num_in_mds();
751 rebalance_time
= ceph_clock_now();
752 mds
->mdcache
->migrator
->clear_export_queue();
754 /* fill in the metrics for each mds by grabbing load struct */
755 vector
< map
<string
, double> > metrics (cluster_size
);
756 for (mds_rank_t i
=mds_rank_t(0);
757 i
< mds_rank_t(cluster_size
);
759 map
<mds_rank_t
, mds_load_t
>::value_type
val(i
, mds_load_t(ceph_clock_now()));
760 std::pair
< map
<mds_rank_t
, mds_load_t
>::iterator
, bool > r(mds_load
.insert(val
));
761 mds_load_t
&load(r
.first
->second
);
763 metrics
[i
] = {{"auth.meta_load", load
.auth
.meta_load()},
764 {"all.meta_load", load
.all
.meta_load()},
765 {"req_rate", load
.req_rate
},
766 {"queue_len", load
.queue_len
},
767 {"cpu_load_avg", load
.cpu_load_avg
}};
770 /* execute the balancer */
772 int ret
= mantle
.balance(bal_code
, mds
->get_nodeid(), metrics
, state
.targets
);
773 dout(2) << " mantle decided that new targets=" << state
.targets
<< dendl
;
775 /* mantle doesn't know about cluster size, so check target len here */
776 if ((int) state
.targets
.size() != cluster_size
)
781 try_rebalance(state
);
787 void MDBalancer::try_rebalance(balance_state_t
& state
)
789 if (g_conf
->mds_thrash_exports
) {
790 dout(5) << "mds_thrash is on; not performing standard rebalance operation!"
795 // make a sorted list of my imports
796 map
<double,CDir
*> import_pop_map
;
797 multimap
<mds_rank_t
,CDir
*> import_from_map
;
798 set
<CDir
*> fullauthsubs
;
800 mds
->mdcache
->get_fullauth_subtrees(fullauthsubs
);
801 for (set
<CDir
*>::iterator it
= fullauthsubs
.begin();
802 it
!= fullauthsubs
.end();
805 if (im
->get_inode()->is_stray()) continue;
807 double pop
= im
->pop_auth_subtree
.meta_load(rebalance_time
, mds
->mdcache
->decayrate
);
808 if (g_conf
->mds_bal_idle_threshold
> 0 &&
809 pop
< g_conf
->mds_bal_idle_threshold
&&
810 im
->inode
!= mds
->mdcache
->get_root() &&
811 im
->inode
->authority().first
!= mds
->get_nodeid()) {
812 dout(0) << " exporting idle (" << pop
<< ") import " << *im
813 << " back to mds." << im
->inode
->authority().first
815 mds
->mdcache
->migrator
->export_dir_nicely(im
, im
->inode
->authority().first
);
819 import_pop_map
[ pop
] = im
;
820 mds_rank_t from
= im
->inode
->authority().first
;
821 dout(15) << " map: i imported " << *im
<< " from " << from
<< dendl
;
822 import_from_map
.insert(pair
<mds_rank_t
,CDir
*>(from
, im
));
828 set
<CDir
*> already_exporting
;
830 for (auto &it
: state
.targets
) {
831 mds_rank_t target
= it
.first
;
832 double amount
= it
.second
;
834 if (amount
< MIN_OFFLOAD
) continue;
835 if (amount
/ target_load
< .2) continue;
837 dout(5) << "want to send " << amount
<< " to mds." << target
838 //<< " .. " << (*it).second << " * " << load_fac
840 << dendl
;//" .. fudge is " << fudge << dendl;
844 mds
->mdcache
->show_subtrees();
846 // search imports from target
847 if (import_from_map
.count(target
)) {
848 dout(5) << " aha, looking through imports from target mds." << target
<< dendl
;
849 pair
<multimap
<mds_rank_t
,CDir
*>::iterator
, multimap
<mds_rank_t
,CDir
*>::iterator
> p
=
850 import_from_map
.equal_range(target
);
851 while (p
.first
!= p
.second
) {
852 CDir
*dir
= (*p
.first
).second
;
853 dout(5) << "considering " << *dir
<< " from " << (*p
.first
).first
<< dendl
;
854 multimap
<mds_rank_t
,CDir
*>::iterator plast
= p
.first
++;
856 if (dir
->inode
->is_base() ||
857 dir
->inode
->is_stray())
859 if (dir
->is_freezing() || dir
->is_frozen()) continue; // export pbly already in progress
860 double pop
= dir
->pop_auth_subtree
.meta_load(rebalance_time
, mds
->mdcache
->decayrate
);
861 assert(dir
->inode
->authority().first
== target
); // cuz that's how i put it in the map, dummy
863 if (pop
<= amount
-have
) {
864 dout(0) << "reexporting " << *dir
866 << " back to mds." << target
<< dendl
;
867 mds
->mdcache
->migrator
->export_dir_nicely(dir
, target
);
869 import_from_map
.erase(plast
);
870 import_pop_map
.erase(pop
);
872 dout(5) << "can't reexport " << *dir
<< ", too big " << pop
<< dendl
;
874 if (amount
-have
< MIN_OFFLOAD
) break;
877 if (amount
-have
< MIN_OFFLOAD
) {
883 for (map
<double,CDir
*>::iterator import
= import_pop_map
.begin();
884 import
!= import_pop_map
.end();
886 CDir
*imp
= (*import
).second
;
887 if (imp
->inode
->is_base() ||
888 imp
->inode
->is_stray())
891 double pop
= (*import
).first
;
892 if (pop
< amount
-have
|| pop
< MIN_REEXPORT
) {
893 dout(0) << "reexporting " << *imp
895 << " back to mds." << imp
->inode
->authority()
898 mds
->mdcache
->migrator
->export_dir_nicely(imp
, imp
->inode
->authority().first
);
900 if (amount
-have
< MIN_OFFLOAD
) break;
902 if (amount
-have
< MIN_OFFLOAD
) {
903 //fudge = amount-have;
907 // okay, search for fragments of my workload
908 set
<CDir
*> candidates
;
909 mds
->mdcache
->get_fullauth_subtrees(candidates
);
913 for (set
<CDir
*>::iterator pot
= candidates
.begin();
914 pot
!= candidates
.end();
916 if ((*pot
)->get_inode()->is_stray()) continue;
917 find_exports(*pot
, amount
, exports
, have
, already_exporting
);
918 if (have
> amount
-MIN_OFFLOAD
)
921 //fudge = amount - have;
923 for (list
<CDir
*>::iterator it
= exports
.begin(); it
!= exports
.end(); ++it
) {
924 dout(0) << " - exporting "
925 << (*it
)->pop_auth_subtree
927 << (*it
)->pop_auth_subtree
.meta_load(rebalance_time
, mds
->mdcache
->decayrate
)
928 << " to mds." << target
931 mds
->mdcache
->migrator
->export_dir_nicely(*it
, target
);
935 dout(5) << "rebalance done" << dendl
;
936 mds
->mdcache
->show_subtrees();
939 void MDBalancer::find_exports(CDir
*dir
,
941 list
<CDir
*>& exports
,
943 set
<CDir
*>& already_exporting
)
945 double need
= amount
- have
;
946 if (need
< amount
* g_conf
->mds_bal_min_start
)
947 return; // good enough!
948 double needmax
= need
* g_conf
->mds_bal_need_max
;
949 double needmin
= need
* g_conf
->mds_bal_need_min
;
950 double midchunk
= need
* g_conf
->mds_bal_midchunk
;
951 double minchunk
= need
* g_conf
->mds_bal_minchunk
;
953 list
<CDir
*> bigger_rep
, bigger_unrep
;
954 multimap
<double, CDir
*> smaller
;
956 double dir_pop
= dir
->pop_auth_subtree
.meta_load(rebalance_time
, mds
->mdcache
->decayrate
);
957 dout(7) << " find_exports in " << dir_pop
<< " " << *dir
<< " need " << need
<< " (" << needmin
<< " - " << needmax
<< ")" << dendl
;
959 double subdir_sum
= 0;
960 for (CDir::map_t::iterator it
= dir
->begin();
963 CInode
*in
= it
->second
->get_linkage()->get_inode();
965 if (!in
->is_dir()) continue;
968 in
->get_dirfrags(dfls
);
969 for (list
<CDir
*>::iterator p
= dfls
.begin();
973 if (!subdir
->is_auth()) continue;
974 if (already_exporting
.count(subdir
)) continue;
976 if (subdir
->is_frozen()) continue; // can't export this right now!
979 double pop
= subdir
->pop_auth_subtree
.meta_load(rebalance_time
, mds
->mdcache
->decayrate
);
981 dout(15) << " subdir pop " << pop
<< " " << *subdir
<< dendl
;
983 if (pop
< minchunk
) continue;
986 if (pop
> needmin
&& pop
< needmax
) {
987 exports
.push_back(subdir
);
988 already_exporting
.insert(subdir
);
994 if (subdir
->is_rep())
995 bigger_rep
.push_back(subdir
);
997 bigger_unrep
.push_back(subdir
);
999 smaller
.insert(pair
<double,CDir
*>(pop
, subdir
));
1002 dout(15) << " sum " << subdir_sum
<< " / " << dir_pop
<< dendl
;
1004 // grab some sufficiently big small items
1005 multimap
<double,CDir
*>::reverse_iterator it
;
1006 for (it
= smaller
.rbegin();
1007 it
!= smaller
.rend();
1010 if ((*it
).first
< midchunk
)
1013 dout(7) << " taking smaller " << *(*it
).second
<< dendl
;
1015 exports
.push_back((*it
).second
);
1016 already_exporting
.insert((*it
).second
);
1017 have
+= (*it
).first
;
1022 // apprently not enough; drill deeper into the hierarchy (if non-replicated)
1023 for (list
<CDir
*>::iterator it
= bigger_unrep
.begin();
1024 it
!= bigger_unrep
.end();
1026 dout(15) << " descending into " << **it
<< dendl
;
1027 find_exports(*it
, amount
, exports
, have
, already_exporting
);
1032 // ok fine, use smaller bits
1034 it
!= smaller
.rend();
1036 dout(7) << " taking (much) smaller " << it
->first
<< " " << *(*it
).second
<< dendl
;
1038 exports
.push_back((*it
).second
);
1039 already_exporting
.insert((*it
).second
);
1040 have
+= (*it
).first
;
1045 // ok fine, drill into replicated dirs
1046 for (list
<CDir
*>::iterator it
= bigger_rep
.begin();
1047 it
!= bigger_rep
.end();
1049 dout(7) << " descending into replicated " << **it
<< dendl
;
1050 find_exports(*it
, amount
, exports
, have
, already_exporting
);
1057 void MDBalancer::hit_inode(utime_t now
, CInode
*in
, int type
, int who
)
1060 in
->pop
.get(type
).hit(now
, mds
->mdcache
->decayrate
);
1062 if (in
->get_parent_dn())
1063 hit_dir(now
, in
->get_parent_dn()->get_dir(), type
, who
);
1066 void MDBalancer::maybe_fragment(CDir
*dir
, bool hot
)
1069 if (g_conf
->mds_bal_frag
&& g_conf
->mds_bal_fragment_interval
> 0 &&
1070 !dir
->inode
->is_base() && // not root/base (for now at least)
1074 if (g_conf
->mds_bal_split_size
> 0 &&
1075 mds
->mdsmap
->allows_dirfrags() &&
1076 (dir
->should_split() || hot
))
1078 if (split_pending
.count(dir
->dirfrag()) == 0) {
1079 queue_split(dir
, false);
1081 if (dir
->should_split_fast()) {
1082 queue_split(dir
, true);
1084 dout(10) << __func__
<< ": fragment already enqueued to split: "
1091 if (dir
->get_frag() != frag_t() && dir
->should_merge() &&
1092 merge_pending
.count(dir
->dirfrag()) == 0) {
1098 void MDBalancer::hit_dir(utime_t now
, CDir
*dir
, int type
, int who
, double amount
)
1101 double v
= dir
->pop_me
.get(type
).hit(now
, amount
);
1103 const bool hot
= (v
> g_conf
->mds_bal_split_rd
&& type
== META_POP_IRD
) ||
1104 (v
> g_conf
->mds_bal_split_wr
&& type
== META_POP_IWR
);
1106 dout(20) << "hit_dir " << type
<< " pop is " << v
<< ", frag " << dir
->get_frag()
1107 << " size " << dir
->get_frag_size() << dendl
;
1109 maybe_fragment(dir
, hot
);
1112 if (type
== META_POP_IRD
&& who
>= 0) {
1113 dir
->pop_spread
.hit(now
, mds
->mdcache
->decayrate
, who
);
1116 double rd_adj
= 0.0;
1117 if (type
== META_POP_IRD
&&
1118 dir
->last_popularity_sample
< last_sample
) {
1119 double dir_pop
= dir
->pop_auth_subtree
.get(type
).get(now
, mds
->mdcache
->decayrate
); // hmm??
1120 dir
->last_popularity_sample
= last_sample
;
1121 double pop_sp
= dir
->pop_spread
.get(now
, mds
->mdcache
->decayrate
);
1122 dir_pop
+= pop_sp
* 10;
1124 //if (dir->ino() == inodeno_t(0x10000000002))
1126 dout(20) << "hit_dir " << type
<< " pop " << dir_pop
<< " spread " << pop_sp
1127 << " " << dir
->pop_spread
.last
[0]
1128 << " " << dir
->pop_spread
.last
[1]
1129 << " " << dir
->pop_spread
.last
[2]
1130 << " " << dir
->pop_spread
.last
[3]
1131 << " in " << *dir
<< dendl
;
1134 if (dir
->is_auth() && !dir
->is_ambiguous_auth()) {
1135 if (!dir
->is_rep() &&
1136 dir_pop
>= g_conf
->mds_bal_replicate_threshold
) {
1138 double rdp
= dir
->pop_me
.get(META_POP_IRD
).get(now
, mds
->mdcache
->decayrate
);
1139 rd_adj
= rdp
/ mds
->get_mds_map()->get_num_in_mds() - rdp
;
1140 rd_adj
/= 2.0; // temper somewhat
1142 dout(0) << "replicating dir " << *dir
<< " pop " << dir_pop
<< " .. rdp " << rdp
<< " adj " << rd_adj
<< dendl
;
1144 dir
->dir_rep
= CDir::REP_ALL
;
1145 mds
->mdcache
->send_dir_updates(dir
, true);
1147 // fixme this should adjust the whole pop hierarchy
1148 dir
->pop_me
.get(META_POP_IRD
).adjust(rd_adj
);
1149 dir
->pop_auth_subtree
.get(META_POP_IRD
).adjust(rd_adj
);
1152 if (dir
->ino() != 1 &&
1154 dir_pop
< g_conf
->mds_bal_unreplicate_threshold
) {
1156 dout(0) << "unreplicating dir " << *dir
<< " pop " << dir_pop
<< dendl
;
1158 dir
->dir_rep
= CDir::REP_NONE
;
1159 mds
->mdcache
->send_dir_updates(dir
);
1165 bool hit_subtree
= dir
->is_auth(); // current auth subtree (if any)
1166 bool hit_subtree_nested
= dir
->is_auth(); // all nested auth subtrees
1169 dir
->pop_nested
.get(type
).hit(now
, amount
);
1171 dir
->pop_nested
.get(META_POP_IRD
).adjust(now
, mds
->mdcache
->decayrate
, rd_adj
);
1174 dir
->pop_auth_subtree
.get(type
).hit(now
, amount
);
1176 dir
->pop_auth_subtree
.get(META_POP_IRD
).adjust(now
, mds
->mdcache
->decayrate
, rd_adj
);
1179 if (hit_subtree_nested
) {
1180 dir
->pop_auth_subtree_nested
.get(type
).hit(now
, mds
->mdcache
->decayrate
, amount
);
1182 dir
->pop_auth_subtree_nested
.get(META_POP_IRD
).adjust(now
, mds
->mdcache
->decayrate
, rd_adj
);
1185 if (dir
->is_subtree_root())
1186 hit_subtree
= false; // end of auth domain, stop hitting auth counters.
1188 if (dir
->inode
->get_parent_dn() == 0) break;
1189 dir
= dir
->inode
->get_parent_dn()->get_dir();
1195 * subtract off an exported chunk.
1196 * this excludes *dir itself (encode_export_dir should have take care of that)
1197 * we _just_ do the parents' nested counters.
1199 * NOTE: call me _after_ forcing *dir into a subtree root,
1200 * but _before_ doing the encode_export_dirs.
1202 void MDBalancer::subtract_export(CDir
*dir
, utime_t now
)
1204 dirfrag_load_vec_t subload
= dir
->pop_auth_subtree
;
1207 dir
= dir
->inode
->get_parent_dir();
1210 dir
->pop_nested
.sub(now
, mds
->mdcache
->decayrate
, subload
);
1211 dir
->pop_auth_subtree_nested
.sub(now
, mds
->mdcache
->decayrate
, subload
);
1216 void MDBalancer::add_import(CDir
*dir
, utime_t now
)
1218 dirfrag_load_vec_t subload
= dir
->pop_auth_subtree
;
1221 dir
= dir
->inode
->get_parent_dir();
1224 dir
->pop_nested
.add(now
, mds
->mdcache
->decayrate
, subload
);
1225 dir
->pop_auth_subtree_nested
.add(now
, mds
->mdcache
->decayrate
, subload
);
1229 void MDBalancer::handle_mds_failure(mds_rank_t who
)
1232 last_epoch_under
= 0;