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>
We currently create a struct chan when we receive a `channel_announcement`,
but we can only broadcast once we have a `channel_update` (since that
provides the timestamp).
This means a `struct chan` can be in a weird state where it exists,
but is unusable (can't use without an update), and also means we need to
keep the channel_announcement message around until an update arrives, so
we can put it in the gossip_store.
Instead, keep track of these "unupdated" channels separately, and check
for them in all the places we search for a specific channel to update.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:30640-33236(32202+/-8.7e+02)
vsz_kb:1812956
store_rewrite_sec:13.410000-16.970000(14.438+/-1.3)
listnodes_sec:0.590000-0.660000(0.62+/-0.033)
listchannels_sec:28.140000-29.560000(28.816+/-0.56)
routing_sec:29.530000-32.590000(30.352+/-1.1)
peer_write_all_sec:60.380000-61.320000(60.836+/-0.37)
MCP notable changes from previous patch (>1 stddev):
-vsz_kb:1812904
+vsz_kb:1812956
-store_rewrite_sec:21.390000-27.070000(23.596+/-2.4)
+store_rewrite_sec:13.410000-16.970000(14.438+/-1.3)
-listnodes_sec:1.120000-1.230000(1.176+/-0.044)
+listnodes_sec:0.590000-0.660000(0.62+/-0.033)
-listchannels_sec:38.900000-50.580000(44.716+/-3.9)
+listchannels_sec:28.140000-29.560000(28.816+/-0.56)
-routing_sec:45.080000-48.160000(46.814+/-1.1)
+routing_sec:29.530000-32.590000(30.352+/-1.1)
-peer_write_all_sec:58.780000-87.150000(72.278+/-9.7)
+peer_write_all_sec:60.380000-61.320000(60.836+/-0.37)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If we have a channel_announcement, we catch any node_announcement for
either end while we validate the channel_announcement. But if we have
multiple channel_announcements and the first one failed to verify, it
would remove this catch, meaning we'd discard following node_announcements
even though there was a pending channel_announcement.
The answer is to use a simple reference count, and as a further
optimization, only place the `pending_node_announce` if there's no
node already.
We also move the process_pending_node_announcement() calls lower down,
so *any* new channel creation checks it. This is more robust, and
will prove useful for the next patch, where we can use the same
mechanism to handle node_announcements on channel_announcements which
are verified, but don't yet have a channel_update.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is currently done higher up, in handle_channel_update(), but
that's one reason why handle_channel_update() has to do a channel
lookup. Moving the check down means handle_channel_update() can do a
minimal "get node id for this channel" so it can check the signature.
This helps, because the chan lookup semantics are changing in the next
few patches.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If we need the payload, pull it from the gossip store.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:30189-52561(39416.4+/-8.8e+03)
vsz_kb:1812904
store_rewrite_sec:21.390000-27.070000(23.596+/-2.4)
listnodes_sec:1.120000-1.230000(1.176+/-0.044)
listchannels_sec:38.900000-50.580000(44.716+/-3.9)
routing_sec:45.080000-48.160000(46.814+/-1.1)
peer_write_all_sec:58.780000-87.150000(72.278+/-9.7)
MCP notable changes from previous patch (>1 stddev):
-vsz_kb:2288784
+vsz_kb:1812904
-store_rewrite_sec:38.060000-39.130000(38.426+/-0.39)
+store_rewrite_sec:21.390000-27.070000(23.596+/-2.4)
-listnodes_sec:0.750000-0.850000(0.794+/-0.042)
+listnodes_sec:1.120000-1.230000(1.176+/-0.044)
-listchannels_sec:30.740000-31.760000(31.096+/-0.35)
+listchannels_sec:38.900000-50.580000(44.716+/-3.9)
-routing_sec:29.600000-33.560000(30.472+/-1.5)
+routing_sec:45.080000-48.160000(46.814+/-1.1)
-peer_write_all_sec:49.220000-52.690000(50.892+/-1.3)
+peer_write_all_sec:58.780000-87.150000(72.278+/-9.7)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Instead of an arbitrary counter, we can use the file offset for our
partial ordering, removing a field. It takes some care when we compact
the store, however, as this field changes.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:34271-35283(34789.6+/-3.3e+02)
vsz_kb:2288784
store_rewrite_sec:38.060000-39.130000(38.426+/-0.39)
listnodes_sec:0.750000-0.850000(0.794+/-0.042)
listchannels_sec:30.740000-31.760000(31.096+/-0.35)
routing_sec:29.600000-33.560000(30.472+/-1.5)
peer_write_all_sec:49.220000-52.690000(50.892+/-1.3)
MCP notable changes from previous patch (>1 stddev):
-store_load_msec:35685-38538(37090.4+/-9.1e+02)
+store_load_msec:34271-35283(34789.6+/-3.3e+02)
-vsz_kb:2288768
+vsz_kb:2288784
-peer_write_all_sec:51.140000-58.350000(55.69+/-2.4)
+peer_write_all_sec:49.220000-52.690000(50.892+/-1.3)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is more compact, but also required once we replace the arbitrary
"index" with an actual offset into the gossip store. That will let us
remove the in-memory variants entirely.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:35685-38538(37090.4+/-9.1e+02)
vsz_kb:2288768
store_rewrite_sec:35.530000-41.230000(37.904+/-2.3)
listnodes_sec:0.720000-0.810000(0.762+/-0.041)
listchannels_sec:30.750000-35.990000(32.704+/-2)
routing_sec:29.570000-34.010000(31.374+/-1.8)
peer_write_all_sec:51.140000-58.350000(55.69+/-2.4)
MCP notable changes from previous patch (>1 stddev):
-vsz_kb:2621808
+vsz_kb:2288768
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We used an s64 so we could use -1 and save a check, but that's just
silly as we have adjacent non-u64 fields: wastes 7 bytes per node
and 16 per channel.
Interestingly, this seemed to make us a little slower for some reason.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:35569-38776(37169.8+/-1.2e+03)
vsz_kb:2621808
store_rewrite_sec:35.870000-40.290000(38.14+/-1.6)
listnodes_sec:0.740000-0.800000(0.768+/-0.023)
listchannels_sec:29.820000-32.730000(30.972+/-0.99)
routing_sec:30.110000-30.590000(30.346+/-0.18)
peer_write_all_sec:52.420000-59.160000(54.692+/-2.5)
MCP notable changes from previous patch (>1 stddev):
-store_load_msec:32825-36365(34615.6+/-1.1e+03)
+store_load_msec:35569-38776(37169.8+/-1.2e+03)
-vsz_kb:2637488
+vsz_kb:2621808
-store_rewrite_sec:35.150000-36.200000(35.59+/-0.4)
+store_rewrite_sec:35.870000-40.290000(38.14+/-1.6)
-listnodes_sec:0.590000-0.710000(0.682+/-0.046)
+listnodes_sec:0.740000-0.800000(0.768+/-0.023)
-peer_write_all_sec:49.020000-52.890000(50.376+/-1.5)
+peer_write_all_sec:52.420000-59.160000(54.692+/-2.5)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We can save significant space by combining both sides: so much that we
can reduce the WIRE_LEN_LIMIT to something sane again.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:34467-36764(35517.8+/-7.7e+02)
vsz_kb:2637488
store_rewrite_sec:35.310000-36.580000(35.816+/-0.44)
listnodes_sec:1.140000-2.780000(1.596+/-0.6)
listchannels_sec:55.390000-58.110000(56.998+/-0.99)
routing_sec:30.330000-30.920000(30.642+/-0.19)
peer_write_all_sec:50.640000-53.360000(51.822+/-0.91)
MCP notable changes from previous patch (>1 stddev):
-store_rewrite_sec:34.720000-35.130000(34.94+/-0.14)
+store_rewrite_sec:35.310000-36.580000(35.816+/-0.44)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Don't turn them to/from pubkeys implicitly. This means nodeids in the store
don't get converted, but bitcoin keys still do.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:33934-35251(34531.4+/-5e+02)
vsz_kb:2637488
store_rewrite_sec:34.720000-35.130000(34.94+/-0.14)
listnodes_sec:1.020000-1.290000(1.146+/-0.086)
listchannels_sec:51.110000-58.240000(54.826+/-2.5)
routing_sec:30.000000-33.320000(30.726+/-1.3)
peer_write_all_sec:50.370000-52.970000(51.646+/-1.1)
MCP notable changes from previous patch (>1 stddev):
-store_load_msec:46184-47474(46673.4+/-4.5e+02)
+store_load_msec:33934-35251(34531.4+/-5e+02)
-vsz_kb:2638880
+vsz_kb:2637488
-store_rewrite_sec:46.750000-48.280000(47.512+/-0.51)
+store_rewrite_sec:34.720000-35.130000(34.94+/-0.14)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
I tried to just do gossipd, but it was uncontainable, so this ended up being
a complete sweep.
We didn't get much space saving in gossipd, even though we should save
24 bytes per node.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Allocating a htable is overkill for most nodes; we can fit 11 pointers
in the same space (10, since we use 1 to indicate we're using an array).
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:45947-47016(46683.4+/-4e+02)
vsz_kb:2639240
store_rewrite_sec:46.950000-49.830000(48.048+/-0.95)
listnodes_sec:1.090000-1.350000(1.196+/-0.095)
listchannels_sec:48.960000-57.640000(53.358+/-2.8)
routing_sec:29.990000-33.880000(31.088+/-1.4)
peer_write_all_sec:49.360000-53.210000(51.338+/-1.4)
MCP notable changes from previous patch (>1 stddev):
- vsz_kb:2641316
+ vsz_kb:2639240
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Makes the next step easier.
MCP results from 5 runs, min-max(mean +/- stddev):
store_load_msec:45791-46917(46330.4+/-3.6e+02)
vsz_kb:2641316
store_rewrite_sec:47.040000-48.720000(47.684+/-0.57)
listnodes_sec:1.140000-1.340000(1.2+/-0.072)
listchannels_sec:50.970000-54.250000(52.698+/-1.3)
routing_sec:29.950000-31.010000(30.332+/-0.37)
peer_write_all_sec:51.570000-52.970000(52.1+/-0.54)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Outputs CSV. We add some stats for load times in developer mode, so we can
easily read them out.
peer_read_all_sec doesn't work, since we seem to reject about half the
updates for having bad signatures. It's also very slow...
routing fails, for unknown reasons, so that failure is ignored in routing_sec.
Results from 5 runs, min-max(mean +/- stddev):
store_load_msec,vsz_kb,store_rewrite_sec,listnodes_sec,listchannels_sec,routing_sec,peer_write_all_sec
39275-44779(40466.8+/-2.2e+03),2899248,41.010000-44.970000(41.972+/-1.5),2.280000-2.350000(2.304+/-0.025),49.770000-63.390000(59.178+/-5),33.310000-34.260000(33.62+/-0.35),42.100000-44.080000(43.082+/-0.67)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Header from folded patch 'fixup!_tools-bench-gossipd.sh__rough_benchmark_for_gossipd_and_the_million_channels_project-2.patch':
fixup! tools/bench-gossipd.sh: rough benchmark for gossipd and the million channels project
Suggested-by: @niftynei
Header from folded patch 'fixup!_tools-bench-gossipd.sh__rough_benchmark_for_gossipd_and_the_million_channels_project-1.patch':
fixup! tools/bench-gossipd.sh: rough benchmark for gossipd and the million channels project
MCP filename change.
Header from folded patch 'tools-bench-gossipd.sh__dont_print_csv_by_default.patch':
tools/bench-gossipd.sh: don't print CSV by default.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Header from folded patch 'fixup!_tools-bench-gossipd.sh__rough_benchmark_for_gossipd_and_the_million_channels_project.patch':
fixup! tools/bench-gossipd.sh: rough benchmark for gossipd and the million channels project
Make shellcheck happy.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rusty Russell
trueptolemy