Merge pull request #1508 from tigerbeetle/dj-vsr-prepare-beyond-check…

…point

VSR: Prepare beyond checkpoint

src/constants.zig

@@ -68,6 +68,7 @@ comptime {
     //   from the previous WAL wrap until a quorum of replicas has reached that checkpoint.
     assert(vsr_checkpoint_interval + lsm_batch_multiple + pipeline_prepare_queue_max <=
         journal_slot_count);
+    assert(vsr_checkpoint_interval >= pipeline_prepare_queue_max);
     assert(vsr_checkpoint_interval >= lsm_batch_multiple);
     assert(vsr_checkpoint_interval % lsm_batch_multiple == 0);
 }

src/vsr.zig

@@ -1400,7 +1400,7 @@ pub const Checkpoint = struct {
         }
     }
 
-    pub fn border_for_checkpoint(checkpoint: u64) ?u64 {
+    pub fn prepare_max_for_checkpoint(checkpoint: u64) ?u64 {
         assert(valid(checkpoint));
 
         if (trigger_for_checkpoint(checkpoint)) |trigger| {