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Retry payment for local failures #4161

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Retry payment for local failures#4161

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@joostjager
joostjager
opened on Oct 15, 2025

When implementing a payment benchmark in ldk-node #664
, I noticed that it is surprisingly difficult to fully saturate a node with payments. One reason is that payments fail immediately if the local channel cannot handle them at that moment, for example when all HTLC slots are filled. The caller, in this case the benchmark code, must then retry. This requires some form of polling, which can create lock contention and slow down the node. To avoid this, the caller has to ensure that not too many payments are initiated simultaneously, which adds complexity.

This made me wonder why LDK does not use the payment timeout window to wait for the local channel to become available again. Especially when the local failure is temporary, such as hitting the maximum HTLC limit, it seems more reasonable to wait rather than forcing the user to poll aggressively.

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Retry payment for local failures · Issue #4161 · lightningdevkit/rust-lightning · GitHub
      Skip to content
      Retry payment for local failures #4161
      Open
      Open
      Retry payment for local failures#4161
      Description
      @joostjager
      joostjager
      opened on Oct 15, 2025
      When implementing a payment benchmark in ldk-node #664
      
, I noticed that it is surprisingly difficult to fully saturate a node with payments. One reason is that payments fail immediately if the local channel cannot handle them at that moment, for example when all HTLC slots are filled. The caller, in this case the benchmark code, must then retry. This requires some form of polling, which can create lock contention and slow down the node. To avoid this, the caller has to ensure that not too many payments are initiated simultaneously, which adds complexity.
      This made me wonder why LDK does not use the payment timeout window to wait for the local channel to become available again. Especially when the local failure is temporary, such as hitting the maximum HTLC limit, it seems more reasonable to wait rather than forcing the user to poll aggressively.
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Retry payment for local failures · Issue #4161 · lightningdevkit/rust-lightning · GitHub
          Skip to content
          Retry payment for local failures #4161
          Open
          Open
          Retry payment for local failures#4161
          Description
          @joostjager
          joostjager
          opened on Oct 15, 2025
          When implementing a payment benchmark in ldk-node #664
          
, I noticed that it is surprisingly difficult to fully saturate a node with payments. One reason is that payments fail immediately if the local channel cannot handle them at that moment, for example when all HTLC slots are filled. The caller, in this case the benchmark code, must then retry. This requires some form of polling, which can create lock contention and slow down the node. To avoid this, the caller has to ensure that not too many payments are initiated simultaneously, which adds complexity.
          This made me wonder why LDK does not use the payment timeout window to wait for the local channel to become available again. Especially when the local failure is temporary, such as hitting the maximum HTLC limit, it seems more reasonable to wait rather than forcing the user to poll aggressively.
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Retry payment for local failures · Issue #4161 · lightningdevkit/rust-lightning · GitHub
              Skip to content
              Retry payment for local failures #4161
              Open
              Open
              Retry payment for local failures#4161
              Description
              @joostjager
              joostjager
              opened on Oct 15, 2025
              When implementing a payment benchmark in ldk-node #664
              
, I noticed that it is surprisingly difficult to fully saturate a node with payments. One reason is that payments fail immediately if the local channel cannot handle them at that moment, for example when all HTLC slots are filled. The caller, in this case the benchmark code, must then retry. This requires some form of polling, which can create lock contention and slow down the node. To avoid this, the caller has to ensure that not too many payments are initiated simultaneously, which adds complexity.
              This made me wonder why LDK does not use the payment timeout window to wait for the local channel to become available again. Especially when the local failure is temporary, such as hitting the maximum HTLC limit, it seems more reasonable to wait rather than forcing the user to poll aggressively.
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var __re = new RegExp('^' + "youtube\\.com" + '
Retry payment for local failures · Issue #4161 · lightningdevkit/rust-lightning · GitHub
                  Skip to content
                  Retry payment for local failures #4161
                  Open
                  Open
                  Retry payment for local failures#4161
                  Description
                  @joostjager
                  joostjager
                  opened on Oct 15, 2025
                  When implementing a payment benchmark in ldk-node #664
                  
, I noticed that it is surprisingly difficult to fully saturate a node with payments. One reason is that payments fail immediately if the local channel cannot handle them at that moment, for example when all HTLC slots are filled. The caller, in this case the benchmark code, must then retry. This requires some form of polling, which can create lock contention and slow down the node. To avoid this, the caller has to ensure that not too many payments are initiated simultaneously, which adds complexity.
                  This made me wonder why LDK does not use the payment timeout window to wait for the local channel to become available again. Especially when the local failure is temporary, such as hitting the maximum HTLC limit, it seems more reasonable to wait rather than forcing the user to poll aggressively.
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, 'i');
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var __re = new RegExp('^' + ".*" + '
Retry payment for local failures · Issue #4161 · lightningdevkit/rust-lightning · GitHub
                      Skip to content
                      Retry payment for local failures #4161
                      Open
                      Open
                      Retry payment for local failures#4161
                      Description
                      @joostjager
                      joostjager
                      opened on Oct 15, 2025
                      When implementing a payment benchmark in ldk-node #664
                      
, I noticed that it is surprisingly difficult to fully saturate a node with payments. One reason is that payments fail immediately if the local channel cannot handle them at that moment, for example when all HTLC slots are filled. The caller, in this case the benchmark code, must then retry. This requires some form of polling, which can create lock contention and slow down the node. To avoid this, the caller has to ensure that not too many payments are initiated simultaneously, which adds complexity.
                      This made me wonder why LDK does not use the payment timeout window to wait for the local channel to become available again. Especially when the local failure is temporary, such as hitting the maximum HTLC limit, it seems more reasonable to wait rather than forcing the user to poll aggressively.
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(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
Retry payment for local failures · Issue #4161 · lightningdevkit/rust-lightning · GitHub
                          Skip to content
                          Retry payment for local failures #4161
                          Open
                          Open
                          Retry payment for local failures#4161
                          Description
                          @joostjager
                          joostjager
                          opened on Oct 15, 2025
                          When implementing a payment benchmark in ldk-node #664
                          
, I noticed that it is surprisingly difficult to fully saturate a node with payments. One reason is that payments fail immediately if the local channel cannot handle them at that moment, for example when all HTLC slots are filled. The caller, in this case the benchmark code, must then retry. This requires some form of polling, which can create lock contention and slow down the node. To avoid this, the caller has to ensure that not too many payments are initiated simultaneously, which adds complexity.
                          This made me wonder why LDK does not use the payment timeout window to wait for the local channel to become available again. Especially when the local failure is temporary, such as hitting the maximum HTLC limit, it seems more reasonable to wait rather than forcing the user to poll aggressively.
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, 'i');
if (__m === '*' || __re.test(location.href)) {
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})();
})();
Retry payment for local failures · Issue #4161 · lightningdevkit/rust-lightning · GitHub
                              Skip to content
                              Retry payment for local failures #4161
                              Open
                              Open
                              Retry payment for local failures#4161
                              Description
                              @joostjager
                              joostjager
                              opened on Oct 15, 2025
                              When implementing a payment benchmark in ldk-node #664
                              
, I noticed that it is surprisingly difficult to fully saturate a node with payments. One reason is that payments fail immediately if the local channel cannot handle them at that moment, for example when all HTLC slots are filled. The caller, in this case the benchmark code, must then retry. This requires some form of polling, which can create lock contention and slow down the node. To avoid this, the caller has to ensure that not too many payments are initiated simultaneously, which adds complexity.
                              This made me wonder why LDK does not use the payment timeout window to wait for the local channel to become available again. Especially when the local failure is temporary, such as hitting the maximum HTLC limit, it seems more reasonable to wait rather than forcing the user to poll aggressively.
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