fd_shredder: fix bug with entry batch sizing

firedancer-io · Mar 25, 2024 · efa9d87 · efa9d87
1 parent 2478a0e
commit efa9d87
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Showing 3 changed files with 43 additions and 6 deletions.
diff --git a/src/disco/shred/fd_shredder.c b/src/disco/shred/fd_shredder.c
@@ -125,7 +125,9 @@ fd_shredder_next_fec_set( fd_shredder_t * shredder,
 
   ulong entry_bytes_remaining = entry_sz - offset;
   /* how many total payload bytes in this FEC set? */
-  ulong chunk_size              = fd_ulong_if( entry_bytes_remaining>=2UL*31200UL, 31200UL, entry_bytes_remaining );
+  ulong chunk_size              = fd_ulong_if( entry_bytes_remaining>=2UL*FD_SHREDDER_NORMAL_FEC_SET_PAYLOAD_SZ,
+                                                                          FD_SHREDDER_NORMAL_FEC_SET_PAYLOAD_SZ,
+                                                                          entry_bytes_remaining );
   ulong data_shred_cnt          = fd_shredder_count_data_shreds( chunk_size );
   ulong parity_shred_cnt        = fd_shredder_count_parity_shreds( chunk_size );
   /* Our notion of tree depth counts the root, while the shred version

diff --git a/src/disco/shred/fd_shredder.h b/src/disco/shred/fd_shredder.h
@@ -111,20 +111,20 @@ void *          fd_shredder_delete( void *          mem      );
    There are two legitimate ways to send certain payload sizes.  We
    always pick the larger value of payload_bytes_per_shred. */
 
-#define NORMAL_FEC_SET_PAYLOAD_SZ (31840UL)
+#define FD_SHREDDER_NORMAL_FEC_SET_PAYLOAD_SZ (31840UL)
 
 FD_FN_CONST static inline ulong
 fd_shredder_count_fec_sets(      ulong sz_bytes ) {
   /* if sz_bytes < 2*31840, we make 1 FEC set.  If sz_bytes is a
      multiple of 31840, we make exactly sz_bytes/31840 sets.  Otherwise,
      we make floor(sz_bytes/31840)-1 normal set + one odd-sized set.
      These cases can be simplified to make it branchless: */
-  return fd_ulong_max( sz_bytes, 2UL*NORMAL_FEC_SET_PAYLOAD_SZ - 1UL ) / NORMAL_FEC_SET_PAYLOAD_SZ;
+  return fd_ulong_max( sz_bytes, 2UL*FD_SHREDDER_NORMAL_FEC_SET_PAYLOAD_SZ - 1UL ) / FD_SHREDDER_NORMAL_FEC_SET_PAYLOAD_SZ;
 }
 FD_FN_CONST static inline ulong
 fd_shredder_count_data_shreds(   ulong sz_bytes ) {
   ulong normal_sets = fd_shredder_count_fec_sets( sz_bytes ) - 1UL;
-  ulong remaining_bytes = sz_bytes - normal_sets * NORMAL_FEC_SET_PAYLOAD_SZ;
+  ulong remaining_bytes = sz_bytes - normal_sets * FD_SHREDDER_NORMAL_FEC_SET_PAYLOAD_SZ;
   ulong shreds = normal_sets * 32UL;
   if(      FD_UNLIKELY( remaining_bytes <=  9135UL ) ) shreds += fd_ulong_max( 1UL, (remaining_bytes + 1014UL)/1015UL );
   else if( FD_LIKELY(   remaining_bytes <= 31840UL ) ) shreds +=                    (remaining_bytes +  994UL)/ 995UL;
@@ -135,15 +135,14 @@ fd_shredder_count_data_shreds(   ulong sz_bytes ) {
 FD_FN_CONST static inline ulong
 fd_shredder_count_parity_shreds( ulong sz_bytes ) {
   ulong normal_sets = fd_shredder_count_fec_sets( sz_bytes ) - 1UL;
-  ulong remaining_bytes = sz_bytes - normal_sets * NORMAL_FEC_SET_PAYLOAD_SZ;
+  ulong remaining_bytes = sz_bytes - normal_sets * FD_SHREDDER_NORMAL_FEC_SET_PAYLOAD_SZ;
   ulong shreds = normal_sets * 32UL;
   if(      FD_UNLIKELY( remaining_bytes <=  9135UL ) ) shreds += fd_shredder_data_to_parity_cnt[ fd_ulong_max( 1UL, (remaining_bytes + 1014UL)/1015UL ) ];
   else if( FD_LIKELY(   remaining_bytes <= 31840UL ) ) shreds += fd_shredder_data_to_parity_cnt[                    (remaining_bytes +  994UL)/ 995UL   ];
   else if( FD_LIKELY(   remaining_bytes <= 62400UL ) ) shreds +=                                                    (remaining_bytes +  974UL)/ 975UL;
   else                                                 shreds +=                                                    (remaining_bytes +  954UL)/ 955UL;
   return shreds;
 }
-#undef NORMAL_FEC_SET_PAYLOAD_SZ
 
 /* fd_shredder_init_batch begins the computation of shreds for an entry
    batch.  shredder must be a valid local join.  entry_batch points to

diff --git a/src/disco/shred/test_shredder.c b/src/disco/shred/test_shredder.c
@@ -180,6 +180,42 @@ test_shredder_count( void ) {
     FD_TEST( fd_shredder_count_parity_shreds( data_sz ) == parity_shreds );
     FD_TEST( fd_shredder_count_fec_sets(      data_sz ) ==      fec_sets );
   }
+
+  /* Now check to make sure the shredder always produces that many
+     shreds. */
+
+  fd_entry_batch_meta_t meta[1];
+  fd_memset( meta, 0, sizeof(fd_entry_batch_meta_t) );
+  signer_ctx_t signer_ctx[ 1 ];
+  signer_ctx_init( signer_ctx, test_private_key );
+
+  FD_TEST( _shredder==fd_shredder_new( _shredder, test_signer, signer_ctx, (ushort)0 ) );
+  fd_shredder_t * shredder = fd_shredder_join( _shredder );           FD_TEST( shredder );
+
+  fd_fec_set_t _set[ 1 ];
+  for( ulong j=0UL; j<FD_REEDSOL_DATA_SHREDS_MAX;   j++ ) _set->data_shreds[   j ] = fec_set_memory_1 + 2048UL*j;
+  for( ulong j=0UL; j<FD_REEDSOL_PARITY_SHREDS_MAX; j++ ) _set->parity_shreds[ j ] = fec_set_memory_2 + 2048UL*j;
+
+  ulong slot=0UL;
+  for( ulong sz=1UL; sz<100000UL; sz++ ) {
+    fd_shredder_init_batch( shredder, perf_test_entry_batch, sz, slot++, meta );
+
+    ulong data_shred_cnt   = 0UL;
+    ulong parity_shred_cnt = 0UL;
+    ulong sets_cnt = fd_shredder_count_fec_sets( sz );
+    for( ulong j=0UL; j<sets_cnt; j++ ) {
+      fd_fec_set_t * set = fd_shredder_next_fec_set( shredder, _set );
+      FD_TEST( set );
+
+      data_shred_cnt   += set->data_shred_cnt;
+      parity_shred_cnt += set->parity_shred_cnt;
+    }
+    FD_TEST( !fd_shredder_next_fec_set( shredder, _set ) );
+    fd_shredder_fini_batch( shredder );
+
+    FD_TEST( data_shred_cnt  ==fd_shredder_count_data_shreds  ( sz ) );
+    FD_TEST( parity_shred_cnt==fd_shredder_count_parity_shreds( sz ) );
+  }
 }
 
 static void