Using jsonrpc_request_sync, layers are loaded before we finish init,
so we never can be asked to create a layer before we've loaded it
(xpay creates a layer immediately on startup).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-None: persistent layers new this release.
Create lower-level versions of routines to create biases, layers,
constraints, etc and only save the ones called from the public APIs.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-None: persistent layers were only added in this release
This lets you place annotated biases on channels, to influence routing.
Uses include avoiding TOR nodes, slow channels or other local preferences.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-None: askrene is new anyway.
Without knowing what method was called, we can't have useful general logging
methods, so go through the pain of adding "const char *method" everywhere,
and add:
1. ignore_and_complete - we're done when jsonrpc returned
2. log_broken_and_complete - we're done, but emit BROKEN log.
3. plugin_broken_cb - if this happens, fail the plugin.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
When we used to allow cmd to be NULL, we had to hand the plugin
everywhere. We no longer do.
1. Various jsonrpc_ functions no longer need the plugin arg.
2. send_outreq no longer needs a plugin arg.
3. The init function takes a command, not a plugin.
4. Remove command_deprecated_in_nocmd_ok.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Since we know the total reservations on each hop, we can more easily
determine probabilities than using flowset_probability() which has to
replicate this collision detection.
We leave both in place for now, to check. The results are not
identical, due to slightly different calculation methods.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
I noticed that increasing mu a little bit sometimes made a big difference,
because by completely ignoring fees we were choosing the worst of two channels
in some cases.
Start at 1% fees; this saves a lot on initial fees in this test!
Here's the new stats on mu levels:
96 mu=1
90 mu=10
41 mu=20
30 mu=30
24 mu=40
19 mu=50
22 mu=60
8 mu=70
95 mu=80
19 mu=90
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-EXPERIMENTAL: `askrene` is now better at finding low-fee paths.
Even after the previous fix, we still occasionally increase fees when my increases.
This is due to the difference between MCF's linear fees, and actual fees, and
is unavoidable, but add a check if it somehow happens.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
I noticed this in the logs:
plugin-cln-askrene: notify msg unusual: The flows had a fee of 151950msat, greater than max of 53697msat, retrying with mu of 10%...
plugin-cln-askrene: notify msg unusual: The flows had a fee of 220126msat, greater than max of 53697msat, retrying with mu of 20%...
We would expect increasing mu to *reduce* the fee!
Turns out that our linear fee is a bad terrible approximation, because I
was using base_fee_penalty of 10.0.
|
| / __ <- real fee, with base: fee = base + propfee * amount.
| / __/
| _//
| __/
| __/_/
|/ _/
| _/ <- linearized fee: fee = linear * amount
|/
+-----------------------------------
These cross over where linear = propfee + base / amount. Assume we split the
payment into 10 parts, this implies that the base_fee_penalty should be 10 / amount
(this gives a slight penalty to the normal case, but that's ok).
This gives better results, too: we get down to 650099 sats in fees, vs 801613
before.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
During "test_real_data", then only successes with reduced fees were 92 on "mu=10", and only
1 on "mu=30": the rest went to mu=100 and failed.
I tried numerous approaches, and in the end, opted for the simplest:
The typical range of probability costs looks likes:
min = 0, max = 924196240, mean = 10509.4, stddev = 1.9e+06
The typical range of linear fee costs looks like:
min = 0, max = 101000000, mean = 81894.6, stddev = 2.6e+06
This implies a k factor of 8 makes the two comparable.
This makes the two numbers comparable, and thus makes "mu" much more
effective. Here are the number of different mu values we succeeded at:
87 mu=0
90 mu=10
42 mu=20
24 mu=30
17 mu=40
19 mu=50
19 mu=60
11 mu=70
95 mu=80
19 mu=90
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We ask it again, but reduce fees by 1msat from the previous answer.
This is really nasty, as it frequently exercises the case where we
only go over fee when we do the refinement step.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The fp16_t values are approximations (overestimate for htlc_max,
underestimate for htlc_min), so in the refinement step we should use
the exact values.
This also fixes a logic bug: flow_remaining_capacity returned the
total capacity, not the additional capacity!
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-EXPERIMENTAL: `askrene` now honors exact htlc_maximum_msat limits.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-EXPERIMENTAL: `getroutes` now applies `auto.sourcefree` layer in the order specified, so doesn't alter channels changed in later layers.
Rather than adding to the gossmap modifications directly, populate
the layer and have the normal layer application logic do it.
This is consistent when we query layers in the next patch.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
And unify logging for better debugging.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-EXPERIMENTAL: `askrene` now has better logging, gives notifications of progress.
The code is a bit too complex for gcc to track it:
```
In file included from ccan/ccan/tal/str/str.h:7,
from plugins/askrene/askrene.c:11:
plugins/askrene/askrene.c: In function ‘do_getroutes’:
ccan/ccan/tal/tal.h:324:23: error: ‘routes’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
324 | #define tal_count(p) (tal_bytelen(p) / sizeof(*p))
| ^~~~~~~~~~~
plugins/askrene/askrene.c:476:24: note: ‘routes’ was declared here
476 | struct route **routes;
| ^~~~~~
plugins/askrene/askrene.c:475:29: error: ‘amounts’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
475 | struct amount_msat *amounts;
| ^~~~~~~
plugins/askrene/askrene.c:488:69: error: ‘probability’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
488 | json_add_u64(response, "probability_ppm", (u64)(probability * 1000000));
| ~~~~~~~~~~~~~^~~~~~~~~~
cc plugins/askrene/dijkstra.c
cc1: all warnings being treated as errors
```
On my local machine, it also warns in param_dev_channel, so I fixed that too.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This turns out to be critical for users: also stops them from
bothering us when their node is offline or has insufficient capacity!
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Lagrang3 points out it's less useful (when we time them out), and probably
a premature optimization anyway.
Suggested-by: Lagrang3 <lagrang3@protonmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This allows for explicit partial updates to channels (e.g. just change
fees, or just disable) without haveing to set the other fields.
This generalizes askrene-disable-channel, which is removed.
We also take the chance to use the proper BOLT 7 terms in the API:
- htlc_minimum_msat
- htlc_maximum_msat
- cltv_expiry_delta
- fee_base_msat
- fee_proportional_millionths
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It was weird not to have a capacity associated with localmods channels, and
fixing it has some very nice side effects.
Now the gossmap_chan_get_capacity() call never fails (we prevented reading
of channels from gossmap in the partially-written case already), so we
make it return the capacity. We do this in msat, because that's what
all the callers want.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is actually what we want in several places: to only override one or
two fields in a channel_update.
We add a gossmap_local_setchan() with a similar API to the old
gossmap_local_updatechan(), for the case where we want to set every
field.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Lagrang3 points out that if we hit a maximum, we should take into account
the reserve. This is true, but it's hard for the caller to do, so change
the API to be slightly higher level.
Tell "inform" what happened, and it adjust the constraints appropriately.
This makes the least assumptions possible (a reserve does *not* mean that
the capacity was actually used at that time).
We also add a mode to say "this succeeded": for now this does nothing,
but it could reduce both min/max capacities, and add capacity in the
other direction. This is useful for future payments, but not as useful
for the current one.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
I got confused, as we had a struct containing two arrays. Simply expose the
reserve_hop struct and use arrays directly.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
It's generally better to be explicit with these things: currently typos
would be ignored. But it's also much easier to clean up entire layers
as we use them for temporary (per-payment) effects.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
askrene.c was getting quite long, and this is self-contained.
The only code change is a convenience accessor for the per-htlc-cost
hash table.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
"spendable" is for a single HTLC: if we own the channel, this amount
decreases with every HTLC, as we have to pay fees. We have access to this since
we call listpeerchannels anyway, so we can calculate the additional costs and
use it in the refining phase.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We don't actually hit the htlc_max cases, since the flow code already
constrains us to that.
And handling htlc_min is better done in the caller, where diagnostics
are better (basically, we should eliminate them, and if that means no
route, give a clear error message).
And the refinement step can handle any extra millisats from rounding.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is the root cause of the problem worked around in 50949b7b9c
"askrene: hack in some padding so we don't overflow capacities."
When adding fees to flows, we didn't recheck the boundary conditions: in
renepay this is done by routebuilder.
Fortunately, we can use our "reservations" infrastructure to temporarily
use capacity as we process flows, so we handle the cases where they are
not independent correclty.
My assumption is that the resulting errors are small, so we divide
them between the remaining flows based on highest-to-least
probability.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Simply calculate it when we need it, which means we don't have to keep it
up-to-date as we tweak the flow.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We had a workaround for channels added by "auto.local", but instead we
should make it work properly.
I didn't do this before because we can't manipulate the localmods while
they're applied, but it's simple to do it in two stages.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
I used `amount_msat_eq(x, AMOUNT_MSAT(0))` because I forgot this
function existed. I probably missed it because the name is surprising,
so add "is" in there to make it clear it's a boolean function.
You'll note almost all the places which did use it are Eduardo's and
Lisa's code, so maybe it's just me.
Fix up a few places which I could use it, too.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Conversion is lossy, and we don't want to spend more than the channel,
so it's conservative to round down here.
This doesn't actually help our test though!
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
You need to know it to make an onion, and in theory if we decided to
fuzz it could be different for different paths.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This populates information on both topology (i.e. unannounced channels) and capacity for the local node using `listpeerchannels`.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
