We do this by keeping a current and an old map, and moving the current to old
every hour or 10,000 entries.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This encoding scheme is no longer just used for short_channel_ids, so make
the names more generic.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
I was seeing some accidental pruning under load / Travis, and in
particular we stopped accepting channel_updates because they were 103
seconds old. But making it too long makes the prune test untenable,
so restore a separate flag that this test can use.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The only real change is dump_gossip() used to call
maybe_create_next_scid_reply(), but now I've simply renamed
that to maybe_send_query_responses() and we call it directly.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Now we queue them, we should place a limit. It's not the worst thing in
the world if we discard them (we'll catch up eventually), but we should
try not to in case we're just a bit behind.
Our behaviour here is also O(n^2) so we don't want a massive queue
anyway.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The first one means we don't discard channels just because we're not
synced, and the second is implied by the spec: don't accept
channel_announcement if the channel isn't 6 deep. Since LND defers in
such cases, we do too (unless it's newer than the current block, in
which case we simply discard). Otherwise there's a risk that a slow
node might discard valid gossip.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This will let gossipd be more intelligent about gossiping before we're
synced, and also it might know how far behind we are.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Happened under Travis with --dev-fast-gossip (90 second prune time), but can
happen anyway if gossip is almost 2 weeks old when we receive it:
2019-09-20T19:16:51.367Z DEBUG lightning_gossipd(20972): Received node_announcement for node 022d223620a359a47ff7f7ac447c85c46c923da53389221a0054c11c1e3ca31d59
2019-09-20T19:16:51.376Z DEBUG lightning_gossipd(20972): Ignoring node_announcement timestamp 1569006918 for 022d223620a359a47ff7f7ac447c85c46c923da53389221a0054c11c1e3ca31d59
2019-09-20T19:16:51.669Z **BROKEN** lightning_gossipd(20972): pending node_announcement 01013094af771d60f4de69bb39ce045e4edf4a06fe6c80078dfa4fab58ab5617d6ad4fa34b6d3437380db0a8293cea348bbc77f714ef71fcd8515bfc82336667441f00005d852546022d223620a359a47ff7f7ac447c85c46c923da53389221a0054c11c1e3ca31d59022d2253494c454e544152544953542d633961313734610000000000000000000000000000 malformed? (version c9a174a)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It's generally clearer to have simple hardcoded numbers with an
#if DEVELOPER around it, than apparent variables which aren't, really.
Interestingly, our pruning test was always kinda broken: we have to pass
two cycles, since l2 will refresh the channel once to avoid pruning.
Do the more obvious thing, and cut the network in half and check that
l1 and l3 time out.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If you send a message which simply changes timestamp and signature, we
drop it. You shouldn't be doing that, and the door to ignoring them
was opened by by option_gossip_query_ex, which would allow clients to
ignore updates with the same checksum.
This is more aggressive at reducing spam messages, but we allow refreshes
(to be conservative, we allow them even when 1/2 of the way through the
refresh period).
I dropped the now-unnecessary sleep from test_gossip_pruning, too.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Make update_local_channel use a timer if it's too soon to make another
update.
1. Implement cupdate_different() which compares two updates.
2. make update_local_channel() take a single arg for timer usage.
3. Set timestamp of non-disable update back 5 minutes, so we can
always generate a disable update if we need to.
4. Make update_local_channel() itself do the "unchanged update" suppression.
gossipd: clean up local channel updates.
5. Keep pointer to the current timer so we override any old updates with
a new one, to avoid a race.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Normally we'd put a pointer into struct half_chan for local
information, but it would be NULL on 99.99% of nodes. Instead, keep a
separate hash table.
This immediately subsumes the previous "map of local-disabled
channels", and will be enhanced further.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Write helpers to split it into non-timestamp, non-signature parts,
and simply compare those. We extract a helper to do channel_update, too.
This is more generic than our previous approach, and simpler.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
For memory-usage reasons, struct chan doesn't use a tal destructor, in
favor of us calling free_chan in the right places.
In DEVELOPER mode, we should check that is the case.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We've been slack, but it's going to be important for testing
ratelimiting. And it currently has a minor memory leak.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rather than reaching into data structures, let them register their own
callbacks. This avoids us having to expose "memleak_remove_xxx"
functions, and call them manually.
Under the hood, this is done by having a specially-named tal child of
the thing we want to assist, containing the callback.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
`make update-mocks` is usually run in DEVELOPER mode, but then it includes
definitions for functions which aren't declared in non-DEVELOPER mode.
We hacked this in a few places, but it's fragile, and worst, now we
have EXPERIMENTAL_FEATURES as well, it's complex.
Instead, declare developer-only functions (but don't define them).
This is a bit more awkward if you accidentally use one in
non-DEVELOPER code (link error rather than compile error), but makes
autogenerating test mocks much easier.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Fortunately, again, only happens with EXPERIMENTAL_FEATURES.
If the query causes us not to actually send anything, we won't
get called again. This can validly happen if they only asked for
the node_announcements, for example.
(Found by protocol tests).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Our "are we finished?" logic was wrong: it tested if there are no more
node_announcements, but it's possible that there were no node_announcements
for either end of the channel whose information we sent.
This is actually quite unusual on the real network: looking at mainnet
statis from last May, 4301 of 4337 nodes have node_announcements.
However, with query flags it's much more likely, since they might not
ask for node announcements at all.
(Found by gossip protocol tests)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
These both allow us to reproduce the test vectors in the next patch. But
using Z_DEFAULT_COMPRESSION is a reasonable idea anyway.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Make the TLV element a simple array. This is a bit neater, in fact, and
makes the test vectors in that 557 PR work.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
In fact, we always generate them, we only send them if asked. And we set
the flags to 0 if not --enable-experimental-features, so we never send in
that case.
Generating checksums involves pulling the channel_update from the
gossip_store, which is suboptimal: there's a FIXME to store the
checksum in memory.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We're about to use the for gossip extended info too, which *don't* put
the encoding byte at the beginning of the data stream. So this removes
some "scids" from function names and separates out the "prepend a byte"
case from the "external encoding_type" case.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
These indicate what fields we are to return. If there's now TLV, or we
haven't got --enable-experimental-features, it's set to all 1s so behaviour
is unchanged.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We ignored this before, which meant that the DEVELOPER-mode check that we
delete the correct record didn't check that it wasn't already deleted.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We always know the length, so we don't need it. It causes much extra work
when we want to delete a record, which I suspect may cause issues amongst
some users who've been seeing gossip_store corruption.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We added a random channel to the list, but we can just free it immediately
(since traversal of a uintmap isn't altered by deletion).
This was introduced in d1f43d993a where we explicitly call free_chan
rather than relying on destructors.
Fixes: #2837
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
==1503== Use of uninitialised value of size 8
==1503== at 0x566786B: _itoa_word (_itoa.c:179)
==1503== by 0x566AF0D: vfprintf (vfprintf.c:1642)
==1503== by 0x569790F: vsnprintf (vsnprintf.c:114)
==1503== by 0x156CCB: do_vfmt (str.c:66)
==1503== by 0x156DB1: tal_vfmt_ (str.c:92)
==1503== by 0x1289CD: status_vfmt (status.c:141)
==1503== by 0x128AAC: status_fmt (status.c:151)
==1503== by 0x118E05: route_prune (routing.c:2495)
==1503== by 0x11DE2D: gossip_refresh_network (gossipd.c:1997)
==1503== by 0x1292B8: timer_expired (timeout.c:39)
==1503== by 0x12088C: main (gossipd.c:3075)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
updates the bolt version to 6639cef095a2ecc7b8f0c48c6e7f2f906fbfbc58.
this requires us to use the new bolt parser at generate-bolt.py
and updates to all of the type specifications (ie. from u8 -> byte)
Rewriting the gossip_store is much more trivial when we don't have
any pointers into it, so add some simple offline compaction code
and disable the automatic compaction code.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The crashes in #2750 are mostly caused by us trying to partially truncate
the store. The simplest fix for release is to discard the whole thing if
we detect a problem.
This is a workaround: it'd be far nicer to try to recover.
Fixes: #2750
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We hit the timestamp assert on #2750; it shouldn't happen, but crashing
doesn't leave much information.
Reported-by: @m-schmook
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If something went wrong and there was an old one, we were
appending to it!
Reported-by: @SimonVrouwe
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We might have channel_announcements which have no channel_update: normally
these don't get written into the store until there is one, but if the
store was truncated it can happen. We then get upset on compaction, since
we don't have an in-memory representation of the channel_announcement.
Similarly, we leave the node_announcement pending until after that
channel_announcement, leading to a similar case.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We can't continue, since we've moved the indexes. We'll just crash
anyway, as seen from bugs #2742 and #2743.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We catch node_announcements for nodes where we haven't finished
analyzing the channel_announcement yet (either because we're still
checking UTXO, or in this case, because we're waiting for a channel_update).
But we reference count the pending_node_announce, so if we have
multiple channels pending, we might try to insert it twice. Clear it
so this doesn't happen.
There's a second bug where we continue to catch node_announcements
until *all* the channel_announcements are no longer pending; this is fixed
by removing it from the map.
Fixes: #2735
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We seek a certain number of peers at each level of gossip; 3 "flood"
if we're missing gossip, 2 at 24 hours past to catch recent gossip, and
8 with current gossip. The rest are given a filter which causes them
not to gossip to us at all.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The first sign that we're missing gossip is that we get a channel_update
for an unknown channel. The peer might be wrong (or lying), but if it turns
out to be a real channel, we were definitely missing something.
This patch does two things: queries when we get an unknown channel_update,
and then notes that a channel_announcement was from such an update when
it's finally processed.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
In particular, we'll need to know the short_channel_id if a
channel_update is unknown (implies we're missing a channel), and whether
processing a pending channel_announcement was successful (implies that
the channel was real).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Up until now we only generated these in dev mode for testing. Hoist
into common code, turn counter into a flag (we're only allowed one!)
and note if query is internal or not.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
I decided to try a faster implementation, only to find our crc32c was
not correct! Ouch.
I removed the crc32c functions from ccan/crc, and added a new crc32c
module which has the Mark Adler x86-64-optimized variants.
We bump gossip_store version again, since csums have changed.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This means there's now a semantic difference between the default `fromid`
and setting `fromid` explicitly to our own node_id. In the default case,
it means we don't charge ourselves fees on the route.
This means we can spend the full channel balance.
We still want to consider the pricing of local channels, however:
there's a *reason* to discount one over another, and that is to bias
things. So we add the first-hop fee to the *risk* value instead.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
(Or, if we crashed before we got to write out the channel_update).
It's a corner case, but one reported by @darosior and reproduced
on my test node (both with bad gossip_store due to previous iterations
of this patchset!).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Triggered by a previous variant of this PR, but a goo1d idea to simply
discard the store in general when we get a duplicate entry.
We crash trying to delete old ones, which means writing to the store.
But they should have already been deleted.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This clarifies things a fair bit: we simply add and remove from the
gossip_store directly.
Before this series: (--disable-developer, -Og)
store_load_msec:20669-20902(20822.2+/-82)
vsz_kb:439704-439712(439706+/-3.2)
listnodes_sec:0.890000-1.000000(0.92+/-0.04)
listchannels_sec:11.960000-13.380000(12.576+/-0.49)
routing_sec:3.070000-5.970000(4.814+/-1.2)
peer_write_all_sec:28.490000-30.580000(29.532+/-0.78)
After: (--disable-developer, -Og)
store_load_msec:19722-20124(19921.6+/-1.4e+02)
vsz_kb:288320
listnodes_sec:0.860000-0.980000(0.912+/-0.056)
listchannels_sec:10.790000-12.260000(11.65+/-0.5)
routing_sec:2.540000-4.950000(4.262+/-0.88)
peer_write_all_sec:17.570000-19.500000(18.048+/-0.73)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We have a problem: if we get halfway through writing the compacted store
and run out of disk space, we've already changed half the indexes.
This changes it so we do nothing until writing is finished: then we
iterate through and update indexes. It also weans us off broadcast
ordering, which we can now eliminated.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We didn't count some records before, so we could compare the two counters.
This is much simpler, and avoids reliance on bs.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This means we intercept the peer's gossip_timestamp_filter request
in the per-peer subdaemon itself. The rest of the semantics are fairly
simple however.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
(We don't increment the gossip_store version, since there are only a
few commits since the last time we did this).
This lets the reader simply filter messages; this is especially nice since
the channel_announcement timestamp is *derived*, not in the actual message.
This also creates a 'struct gossip_hdr' which makes the code a bit
clearer.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Keeping the uintmap ordering all the broadcastable messages is expensive:
130MB for the million-channels project. But now we delete obsolete entries
from the store, we can have the per-peer daemons simply read that sequentially
and stream the gossip itself.
This is the most primitive version, where all gossip is streamed;
successive patches will bring back proper handling of timestamp filtering
and initial_routing_sync.
We add a gossip_state field to track what's happening with our gossip
streaming: it's initialized in gossipd, and currently always set, but
once we handle timestamps the per-peer daemon may do it when the first
filter is sent.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
There's a corner case where otherwise a reader could see the header and
not the body of a message. It could handle that in various ways,
but simplest (and most efficient) is to avoid it happening.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
They already send *us* gossip messages, so they have to be distinct anyway.
Why make us both do extra work?
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We use the high bit of the length field: this way we can still check
that the checksums are valid on deleted fields.
Once this is done, serially reading the gossip_store file will result
in a complete, ordered, minimal gossip broadcast. Also, the horrible
corner case where we might try to delete things from the store during
load time is completely gone: we only load non-deleted things.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We're about to bump version again, and the code to upgrade it was
quite hairy (and buggy!). It's not worthwhile for such a
poorly-tested path: I will just add code to limit how much incoming
gossip we get to avoid flooding when we upgrade, however.
I also use a modern gossip_store version in our test_gossip_store_load
test, instead of relying on the upgrade path.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
They're really gossipd-internal, and we don't want per-peer daemons
to confuse them with normal updates.
I don't bump the gossip_store version; that's coming with another update
anyway.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Now we handle node_announcements properly, we have a failure case where we
try to move them when a channel is deleted while loading the store.
We're going to remove this soon, in favor of in-place delete, so
workaround this for now to avoid an assert() when we try to write to
the store while loading.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When we first receive a channel_update, we write both the
channel_announcement and that channel_update to the store: we need
that first update so we can set the channel_announcement timestamp.
However, the channel_update can be replaced later. This means we can
have a channel_announcement, a node_update which relies on it, then
the channel_update later.
So move the "this applies to a pending announcement" check lower, where
gossip_store can use it too. Has a nice side-effect of avoiding
one lookup of the node id.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It turns out that we don't look at type when we return 0, but gcc isn't
quite smart enough for that. Initializing to -1 is good practice anyway
for the failure path.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Fix a path where tal_free is called on an uninitialized variable
If the first `goto bad_total` executes, then that path has
uninitialized `short_route` but bad_total passes through to `out`
whose first call is tal_free(short_route).
This was noticed by a maybe-uninitialized heuristic on gcc 7.4.0:
gossipd/routing.c: In function ‘find_shorter_route’:
gossipd/routing.c:1096:2: error: ‘short_route’ may be used
uninitialized in this function [-Werror=maybe-uninitialized]
tal_free(short_route);
Reported-by: @ZmnSCPxj <https://github.com/ElementsProject/lightning/pull/2674#issuecomment-495617253>
Signed-off-by: William Casarin <jb55@jb55.com>
Each destructor2 costs 40 bytes, and struct chan is only 120 bytes. So
this drops our memory usage quite a bit:
MCP bench results change:
-vsz_kb:580004-580016(580006+/-4.8)
+vsz_kb:533148
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This has two effects: most importantly, it avoids the problem where
lightningd creates a 800MB JSON blob in response to listchannels,
which causes OOM on the Raspberry Pi (our previous max allocation was
832MB). This is because lightning-cli can start draining the JSON
while we're filling the buffer, so we end up with a max allocation of
68MB.
But despite being less efficient (multiple queries to gossipd), it
actually speeds things up due to the parallelism:
MCP with -O3 -flto before vs after:
-listchannels_sec:8.980000-9.330000(9.206+/-0.14)
+listchannels_sec:7.500000-7.830000(7.656+/-0.11)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We now have a test blockchain for MCP which has the correct channels,
so this is not needed.
Also fix a benchmark script bug where 'mv "$DIR"/log
"$DIR"/log.old.$$' would fail if you log didn't exist from a previous run.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Instead of reading the store ourselves, we can just send them an
offset. This saves gossipd a lot of work, putting it where it belongs
(in the daemon responsible for the specific peer).
MCP bench results:
store_load_msec:28509-31001(29206.6+/-9.4e+02)
vsz_kb:580004-580016(580006+/-4.8)
store_rewrite_sec:11.640000-12.730000(11.908+/-0.41)
listnodes_sec:1.790000-1.880000(1.83+/-0.032)
listchannels_sec:21.180000-21.950000(21.476+/-0.27)
routing_sec:2.210000-11.160000(7.126+/-3.1)
peer_write_all_sec:36.270000-41.200000(38.168+/-1.9)
Signficant savings in streaming gossip:
-peer_write_all_sec:48.160000-51.480000(49.608+/-1.1)
+peer_write_all_sec:35.780000-37.980000(36.43+/-0.81)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We need to store the channel capacity for channel_announcement: hand it
in directly rather than having the gossip_store code do a lookup.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Save some overhead, plus gets us ready for giving subdaemons direct
store access. This is the first time we *upgrade* the gossip_store,
rather than just discarding.
The downside is that we need to add an extra message after each
channel_announcement, containing the channel capacity.
After:
store_load_msec:28337-30288(28975+/-7.4e+02)
vsz_kb:582304-582316(582306+/-4.8)
store_rewrite_sec:11.240000-11.800000(11.55+/-0.21)
listnodes_sec:1.800000-1.880000(1.84+/-0.028)
listchannels_sec:22.690000-26.260000(23.878+/-1.3)
routing_sec:2.280000-9.570000(6.842+/-2.8)
peer_write_all_sec:48.160000-51.480000(49.608+/-1.1)
Differences:
-vsz_kb:582320
+vsz_kb:582316
-listnodes_sec:2.100000-2.170000(2.118+/-0.026)
+listnodes_sec:1.800000-1.880000(1.84+/-0.028)
-peer_write_all_sec:51.600000-52.550000(52.188+/-0.34)
+peer_write_all_sec:48.160000-51.480000(49.608+/-1.1)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We know exactly how many there will be, so allocate an entire array up-front.
-listnodes_sec:2.540000-2.610000(2.584+/-0.029)
+listnodes_sec:2.100000-2.170000(2.118+/-0.026)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Entries we've already loaded expect to exist in the store. We could go
back and remove them all, but instead just truncate at the known-good
point.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Some tests require dev support, but the rest can run. We simplify
the gossip_store output so it's the same in non-dev mode too.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Now we can benchmark, and remove 500 bytes per node.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:35093-37907(36146+/-1.1e+03)
vsz_kb:555168
store_rewrite_sec:12.120000-13.750000(12.7+/-0.6)
listnodes_sec:1.270000-1.370000(1.322+/-0.039)
listchannels_sec:29.770000-31.600000(30.82+/-0.64)
routing_sec:0.00
peer_write_all_sec:63.630000-67.850000(65.432+/-1.7)
MCP notable changes from pre-Dijkstra (>1 stddev):
-vsz_kb:577456
+vsz_kb:555168
-routing_sec:60.70
+routing_sec:12.04
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Do it inside the can_reach() function, which is less optimal for BFG
which does 20 ops on the same channel, but fine for Dijkstra.
This does have a measurable cost, so we might want to use
non-cryptographic fuzz in future:
$ gossipd/test/run-bench-find_route 100000 100:
Before:
100 (100 succeeded) routes in 100000 nodes in 97346 msec (973461784 nanoseconds per route)
After:
100 (100 succeeded) routes in 100000 nodes in 113381 msec (1133813412 nanoseconds per route)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If a route is too long, we try to bias Dijkstra towards choosing a
shorter route by adding a per-hop cost. We do a naive "shortest path"
pass, then using that cost as a ceiling on per-hop cost, we do a
binary search.
There are some subtleties: we use risk rather than total as our
counter field (we normally bias this by 1 anyway, so it's easy to make
that a variable), and we set riskfactor to a mimimal value once we're
iterating. It's good enough to get a solution, we don't need to do a
2-dimensional search on riskfactor and riskbias.
Of course, this is extremely slow if we hit it on our benchmark,
though it doesn't happen in a more realistic network:
$ gossipd/test/run-bench-find_route 100000 100:
Before:
100 (79 succeeded) routes in 100000 nodes in 25341 msec (253412314 nanoseconds per route)
After:
100 (100 succeeded) routes in 100000 nodes in 97346 msec (973461784 nanoseconds per route)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Our uintmap can be a little slow with all the reallocation, so leave
NULL entries and walk to find the first one. Since we don't clean
them up, keep a cache of where the min non-all-NULL value is in the
heap.
It's clearer benefit on really large tests, so here's 1M nodes:
Comparison using gossipd/test/run-bench-find_route 1000000 10:
Before:
10 (10 succeeded) routes in 1000000 nodes in 91995 msec (9199532898 nanoseconds per route)
After:
10 (10 succeeded) routes in 1000000 nodes in 20605 msec (2060539287 nanoseconds per route)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Use a uintmap as our minheap.
Note that Dijkstra can give overlength routes, so some checks are disabled.
Comparison using gossipd/test/run-bench-find_route 100000 10:
Before:
10 (10 succeeded) routes in 100000 nodes in 120087 msec (12008708402 nanoseconds per route)
After:
10 (10 succeeded) routes in 100000 nodes in 2269 msec (226925462 nanoseconds per route)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is a weakness with Dijkstra, so write an explicit unit test that
we can find a short enough (but more expensive) route.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When we compact the store, we need to adjust the broadast index for
peers so they know where they're up to.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This requires some trickiness when we want to re-add unannounced channels
to the store after compaction, so we extract a common "copy_message" to
transfer from old store to new.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:36034-37853(37109.8+/-5.9e+02)
vsz_kb:577456
store_rewrite_sec:12.490000-13.250000(12.862+/-0.27)
listnodes_sec:1.250000-1.480000(1.364+/-0.09)
listchannels_sec:30.820000-31.480000(31.068+/-0.24)
routing_sec:26.940000-27.990000(27.616+/-0.39)
peer_write_all_sec:65.690000-68.600000(66.698+/-0.99)
MCP notable changes from previous patch (>1 stddev):
-vsz_kb:1202316
+vsz_kb:577456
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The next patch causes us to access the store while loading (we read
channel_updates for local peers), which messes up loading due to the
lseek involved.
Using pread() is atomic with seek & read, and also a bit more
efficient. Make the header contiguous too, while we're here.
We don't need pwrite: we always open with O_APPEND which means the
seek-to-end is implicit.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:36771-38289(37529.6+/-5.3e+02)
vsz_kb:1202316
store_rewrite_sec:12.460000-13.280000(12.784+/-0.29)
listnodes_sec:1.240000-1.410000(1.34+/-0.058)
listchannels_sec:29.850000-31.840000(30.908+/-0.69)
routing_sec:27.800000-31.790000(28.822+/-1.5)
peer_write_all_sec:66.200000-68.720000(67.44+/-0.84)
MCP notable changes from previous patch (>1 stddev):
-store_load_msec:39207-45089(41374.6+/-2.2e+03)
+store_load_msec:36771-38289(37529.6+/-5.3e+02)
-store_rewrite_sec:15.090000-16.790000(15.654+/-0.63)
+store_rewrite_sec:12.460000-13.280000(12.784+/-0.29)
-peer_write_all_sec:66.830000-76.850000(71.976+/-3.6)
+peer_write_all_sec:66.200000-68.720000(67.44+/-0.84)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When we no longer keep channel_updates in memory, there's a path where
we access them on load: when we promote a local channel to an
announced channel.
This breaks at the moment, since gs->fd == -1; change it to a writable
flag instead.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The txout_script field is unused; the local_disable only applies to
the handful of local channels, so move that into a hash table.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:39207-45089(41374.6+/-2.2e+03)
vsz_kb:1202316
store_rewrite_sec:15.090000-16.790000(15.654+/-0.63)
listnodes_sec:1.290000-3.790000(1.938+/-0.93)
listchannels_sec:30.190000-32.120000(31.31+/-0.69)
routing_sec:28.220000-31.340000(29.314+/-1.2)
peer_write_all_sec:66.830000-76.850000(71.976+/-3.6)
MCP notable changes from previous patch (>1 stddev):
-store_load_msec:35107-37944(36686+/-1e+03)
+store_load_msec:39207-45089(41374.6+/-2.2e+03)
-vsz_kb:1218036
+vsz_kb:1202316
-listchannels_sec:28.510000-30.270000(29.6+/-0.6)
+listchannels_sec:30.190000-32.120000(31.31+/-0.69)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We used to have a `struct chan` while we're waiting for an update; now we
keep that internally. So a `struct chan` without a channel_announcement
in the store is private, and other is public.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Reload them from disk if they do listnodes.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:35390-38659(37336.4+/-1.3e+03)
vsz_kb:1780516
store_rewrite_sec:13.800000-16.800000(15.02+/-0.98)
listnodes_sec:1.280000-1.530000(1.382+/-0.096)
listchannels_sec:28.700000-30.440000(29.34+/-0.68)
routing_sec:30.120000-31.080000(30.526+/-0.35)
peer_write_all_sec:65.910000-76.850000(69.462+/-4.1)
MCP notable changes from previous patch (>1 stddev):
-vsz_kb:1792996
+vsz_kb:1780516
-listnodes_sec:1.030000-1.120000(1.068+/-0.032)
+listnodes_sec:1.280000-1.530000(1.382+/-0.096)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rusty Russell
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