ci: add epoch boundary time to the PR benchmark comment

.github/workflows/benchmark.yml

@@ -13,11 +13,18 @@ on:
         type: string
         default: testnet-455087014-snapload
         description: 'load-only testnet ledger (genesis.bin + full snapshot) for the snapshot row'
+      epoch-ledger:
+        type: string
+        default: mainnet-epoch-boundary-461376000
+        description: 'minimized mainnet ledger whose first replayed slots cross an epoch boundary, for the epoch row'
   workflow_dispatch:
     inputs:
       snapshot-ledger:
         type: string
         default: testnet-455087014-snapload
+      epoch-ledger:
+        type: string
+        default: mainnet-epoch-boundary-461376000
 
 permissions:
   contents: read
@@ -158,6 +165,7 @@ jobs:
       BENCH_DIR: ${{ github.workspace }}/../bench
       DUMP_DIR: ${{ github.workspace }}/../dump
       BENCH_SNAP_LEDGER: ${{ inputs.snapshot-ledger }}
+      BENCH_EPOCH_LEDGER: ${{ inputs.epoch-ledger }}
 
     steps:
     - uses: actions/checkout@v7
@@ -223,6 +231,9 @@ jobs:
     - run: contrib/ci/bench/bench.sh snapshot base
       continue-on-error: true  # a baseline that cannot run is not the PR's fault; its rows stay pending
     - run: contrib/ci/bench/bench.sh snapshot new
+    - run: contrib/ci/bench/bench.sh epoch base
+      continue-on-error: true
+    - run: contrib/ci/bench/bench.sh epoch new
     - name: Free RAM disk  # brd keeps its pages until rmmod
       if: always()
       continue-on-error: true

.github/workflows/on_pull_request.yml

@@ -27,6 +27,7 @@ jobs:
     with:
       github-token: ${{ github.token }}
       snapshot-ledger: testnet-455087014-snapload
+      epoch-ledger: mainnet-epoch-boundary-461376000
     secrets: inherit
   build_checks_1:
     if: github.event.pull_request.draft == false

contrib/ci/bench/bench.sh

@@ -1,8 +1,8 @@
 #!/bin/bash
-# PR perf rows.  bench.sh build|replay|snapshot|bench base|new
+# PR perf rows.  bench.sh build|replay|snapshot|epoch|bench base|new
 # Raw results land in $BENCH_DIR/<side>.<what>.*; benchmark_comment.py turns them into the comment.
 set -euo pipefail
-what=${1:?usage: bench.sh build|replay|snapshot|bench base|new} side=${2:?side}
+what=${1:?usage: bench.sh build|replay|snapshot|epoch|bench base|new} side=${2:?side}
 BENCH_DIR=${BENCH_DIR:-$(realpath ..)/bench}
 DUMP_DIR=${DUMP_DIR:-$(realpath ..)/dump}
 SHREDB=/dev/shm/fd-bench-shreds.db  # tmpfs: on disk, writeback holds its inode lock and stalls shred/rserve pwrite() for whole slots
@@ -76,6 +76,7 @@ case $what in
       ACCOUNTS_DB=$RAMDB/accounts.db out=$out.warmup backtest "${BENCH_SNAP_LEDGER:?}" -m 100000000
     fi
     ACCOUNTS_DB=$RAMDB/accounts.db backtest "${BENCH_SNAP_LEDGER:?}" -m 100000000 ;;
+  epoch)    backtest "${BENCH_EPOCH_LEDGER:-mainnet-epoch-boundary-461376000}" -m 2000000 ;;  # whole ledger: crosses one epoch boundary
   bench)
     { cat "$BENCH_DIR/$side/bench.toml"; printf '[paths]\n    accounts = "%s"\n    shredb = "%s"\n' "$DUMP_DIR/accounts.db" "$SHREDB"; } > "$out.toml"
     quiesce

contrib/ci/bench/benchmark_comment.py

@@ -28,6 +28,12 @@ def snapshot_load(d, s):
     log = read(d, s, "snapshot.log")
     return (stamp(log, "replay ready at slot") - stamp(log, "reading full snapshot from file")) % 86400  # midnight
 
+def epoch_boundary(d, s):  # ms fd_runtime_process_new_epoch() took at the boundary the epoch ledger crosses
+    log = re.sub(r"\x1b\[[0-9;]*m", "", read(d, s, "epoch.log"))  # the runtime styles this line when colorized
+    took = re.findall(r"starting epoch \d+ at slot \d+ \(took ([0-9.]+) seconds\)", log)
+    if not took: raise LookupError("epoch.log: no epoch boundary")
+    return float(took[-1]) * 1e3
+
 def mem(d, s, cluster):
     return json.loads(read(d, s, f"build.mem.{cluster}.json"))["summary"]["total_memory_locked_bytes"] / 2**30
 
@@ -36,12 +42,13 @@ def mem(d, s, cluster):
     ("replay_tps",    "replay tps, mainnet",       "replay",   lambda d, s: summary(d, s, "replay")["tps"],                ",.0f tps",  1.25,  2.5, True),
     ("bench_tps",     "bench tps, localnet",       "bench",    lambda d, s: summary(d, s, "bench")["tps"],                 ",.0f tps",  1.75,  3.5, True),
     ("snapshot_load", "snapshot load, testnet",    "snapshot", snapshot_load,                                              ".2f s",      1.5,  3.0, False),
+    ("epoch_boundary","epoch boundary, mainnet",   "snapshot", epoch_boundary,                                             ".1f ms",     5.0, 10.0, False),
     ("mem_mainnet",   "mem total, mainnet",        "replay",   lambda d, s: mem(d, s, "mainnet"),                          ".2f GiB",    0.0,  1.0, False),
     ("mem_testnet",   "mem total, testnet",        "replay",   lambda d, s: mem(d, s, "testnet"),                          ".2f GiB",    0.0,  1.0, False),
     ("compile",       "clean compile, firedancer", "*",        lambda d, s: float(read(d, s, "build.time").split()[0]),   ".2f s",       1.5,  3.0, False),
     ("binsize",       "binary size, firedancer",   "replay",   lambda d, s: os.path.getsize(f"{d}/{s}/bin/firedancer") / 1e6, ".2f MB",  0.5,  2.0, False),
 )
-HIST_HDR = ("TPS", "BENCH", "SNAP", "MEM·M", "MEM·T", "COMPILE", "BINARY")
+HIST_HDR = ("TPS", "BENCH", "SNAP", "EPOCH", "MEM·M", "MEM·T", "COMPILE", "BINARY")
 
 def tier(row, d):
     _, _, _, _, _, warn, red, up = row