shrink batches when over 80% of the space is wasted

core/benches/sigverify_stage.rs

@@ -9,7 +9,7 @@ use {
     log::*,
     rand::{thread_rng, Rng},
     solana_core::{sigverify::TransactionSigVerifier, sigverify_stage::SigVerifyStage},
-    solana_perf::{packet::to_packet_batches, test_tx::test_tx},
+    solana_perf::{packet::to_packet_batches, packet::PacketBatch, test_tx::test_tx},
     solana_sdk::{
         hash::Hash,
         signature::{Keypair, Signer},
@@ -109,19 +109,10 @@ fn bench_packet_discard_mixed_senders(bencher: &mut Bencher) {
     });
 }
 
-#[bench]
-fn bench_sigverify_stage(bencher: &mut Bencher) {
-    solana_logger::setup();
-    let (packet_s, packet_r) = unbounded();
-    let (verified_s, verified_r) = unbounded();
-    let verifier = TransactionSigVerifier::default();
-    let stage = SigVerifyStage::new(packet_r, verified_s, verifier);
-
-    let now = Instant::now();
+fn gen_batches(use_same_tx: bool) -> Vec<PacketBatch> {
     let len = 4096;
-    let use_same_tx = true;
     let chunk_size = 1024;
-    let mut batches = if use_same_tx {
+    if use_same_tx {
         let tx = test_tx();
         to_packet_batches(&vec![tx; len], chunk_size)
     } else {
@@ -139,14 +130,28 @@ fn bench_sigverify_stage(bencher: &mut Bencher) {
             })
             .collect();
         to_packet_batches(&txs, chunk_size)
-    };
+    }
+}
 
-    trace!(
-        "starting... generation took: {} ms batches: {}",
-        duration_as_ms(&now.elapsed()),
-        batches.len()
-    );
+#[bench]
+fn bench_sigverify_stage(bencher: &mut Bencher) {
+    solana_logger::setup();
+    trace!("start");
+    let (packet_s, packet_r) = unbounded();
+    let (verified_s, verified_r) = unbounded();
+    let verifier = TransactionSigVerifier::default();
+    let stage = SigVerifyStage::new(packet_r, verified_s, verifier);
+
+    let use_same_tx = true;
     bencher.iter(move || {
+        let now = Instant::now();
+        let mut batches = gen_batches(use_same_tx);
+        trace!(
+            "starting... generation took: {} ms batches: {}",
+            duration_as_ms(&now.elapsed()),
+            batches.len()
+        );
+
         let mut sent_len = 0;
         for _ in 0..batches.len() {
             if let Some(batch) = batches.pop() {
@@ -162,7 +167,7 @@ fn bench_sigverify_stage(bencher: &mut Bencher) {
                     received += v.packets.len();
                     batches.push(v);
                 }
-                if received >= sent_len {
+                if use_same_tx || received >= sent_len {
                     break;
                 }
             }

core/src/sigverify_stage.rs

@@ -12,7 +12,7 @@ use {
     itertools::Itertools,
     solana_measure::measure::Measure,
     solana_perf::packet::PacketBatch,
-    solana_perf::sigverify::Deduper,
+    solana_perf::sigverify::{count_valid_packets, shrink_batches, Deduper},
     solana_sdk::timing,
     solana_streamer::streamer::{self, PacketBatchReceiver, StreamerError},
     std::{
@@ -58,6 +58,9 @@ struct SigVerifierStats {
     total_packets: usize,
     total_dedup: usize,
     total_excess_fail: usize,
+    total_shrink_time: usize,
+    total_shrinks: usize,
+    total_valid_packets: usize,
 }
 
 impl SigVerifierStats {
@@ -166,6 +169,9 @@ impl SigVerifierStats {
             ("total_packets", self.total_packets, i64),
             ("total_dedup", self.total_dedup, i64),
             ("total_excess_fail", self.total_excess_fail, i64),
+            ("total_shrink_time", self.total_shrink_time, i64),
+            ("total_shrinks", self.total_shrinks, i64),
+            ("total_valid_packets", self.total_valid_packets, i64),
         );
     }
 }
@@ -248,7 +254,20 @@ impl SigVerifyStage {
         discard_time.stop();
 
         let mut verify_batch_time = Measure::start("sigverify_batch_time");
-        let batches = verifier.verify_batches(batches, num_valid_packets);
+        let mut batches = verifier.verify_batches(batches, num_valid_packets);
+        verify_batch_time.stop();
+
+        let mut shrink_time = Measure::start("sigverify_shrink_time");
+        let num_valid_packets = count_valid_packets(&batches);
+        let start_len = batches.len();
+        const MAX_EMPTY_BATCH_RATIO: usize = 4;
+        if num_packets > num_valid_packets.saturating_mul(MAX_EMPTY_BATCH_RATIO) {
+            let valid = shrink_batches(&mut batches);
+            batches.truncate(valid);
+        }
+        let total_shrinks = start_len.saturating_sub(batches.len());
+        shrink_time.stop();
+
         sendr.send(batches)?;
         verify_batch_time.stop();
 
@@ -282,7 +301,10 @@ impl SigVerifyStage {
         stats.total_batches += batches_len;
         stats.total_packets += num_packets;
         stats.total_dedup += dedup_fail;
+        stats.total_valid_packets += num_valid_packets;
         stats.total_excess_fail += excess_fail;
+        stats.total_shrink_time += shrink_time.as_us() as usize;
+        stats.total_shrinks += total_shrinks;
 
         Ok(())
     }
@@ -348,6 +370,11 @@ impl SigVerifyStage {
 
 #[cfg(test)]
 mod tests {
+    use crate::sigverify::TransactionSigVerifier;
+    use crate::sigverify_stage::timing::duration_as_ms;
+    use crossbeam_channel::unbounded;
+    use solana_perf::packet::to_packet_batches;
+    use solana_perf::test_tx::test_tx;
     use {super::*, solana_perf::packet::Packet};
 
     fn count_non_discard(packet_batches: &[PacketBatch]) -> usize {
@@ -379,4 +406,58 @@ mod tests {
         assert!(batches[0].packets[3].meta.discard());
         assert!(!batches[0].packets[4].meta.discard());
     }
+    fn gen_batches(use_same_tx: bool) -> Vec<PacketBatch> {
+        let len = 4096;
+        let chunk_size = 1024;
+        if use_same_tx {
+            let tx = test_tx();
+            to_packet_batches(&vec![tx; len], chunk_size)
+        } else {
+            let txs: Vec<_> = (0..len).map(|_| test_tx()).collect();
+            to_packet_batches(&txs, chunk_size)
+        }
+    }
+
+    #[test]
+    fn test_sigverify_stage() {
+        solana_logger::setup();
+        trace!("start");
+        let (packet_s, packet_r) = unbounded();
+        let (verified_s, verified_r) = unbounded();
+        let verifier = TransactionSigVerifier::default();
+        let stage = SigVerifyStage::new(packet_r, verified_s, verifier);
+
+        let use_same_tx = true;
+        let now = Instant::now();
+        let mut batches = gen_batches(use_same_tx);
+        trace!(
+            "starting... generation took: {} ms batches: {}",
+            duration_as_ms(&now.elapsed()),
+            batches.len()
+        );
+
+        let mut sent_len = 0;
+        for _ in 0..batches.len() {
+            if let Some(batch) = batches.pop() {
+                sent_len += batch.packets.len();
+                packet_s.send(batch).unwrap();
+            }
+        }
+        let mut received = 0;
+        trace!("sent: {}", sent_len);
+        loop {
+            if let Ok(mut verifieds) = verified_r.recv_timeout(Duration::from_millis(10)) {
+                while let Some(v) = verifieds.pop() {
+                    received += v.packets.len();
+                    batches.push(v);
+                }
+                if use_same_tx || received >= sent_len {
+                    break;
+                }
+            }
+        }
+        trace!("received: {}", received);
+        drop(packet_s);
+        stage.join().unwrap();
+    }
 }

perf/benches/shrink.rs

@@ -0,0 +1,86 @@
+#![allow(clippy::integer_arithmetic)]
+#![feature(test)]
+
+extern crate test;
+
+use {
+    rand::prelude::*,
+    solana_perf::{
+        packet::{to_packet_batches, PacketBatch, PACKETS_PER_BATCH},
+        sigverify,
+    },
+    test::Bencher,
+};
+
+const NUM_PACKETS: usize = 1024 * 4;
+
+fn test_packet_with_size(size: usize, rng: &mut ThreadRng) -> Vec<u8> {
+    // subtract 8 bytes because the length will get serialized as well
+    (0..size.checked_sub(8).unwrap())
+        .map(|_| rng.gen())
+        .collect()
+}
+
+fn do_bench_shrink_packets(bencher: &mut Bencher, mut batches: Vec<PacketBatch>) {
+    // verify packets
+    bencher.iter(|| {
+        let _ans = sigverify::shrink_batches(&mut batches);
+        batches.iter_mut().for_each(|b| {
+            b.packets
+                .iter_mut()
+                .for_each(|p| p.meta.set_discard(thread_rng().gen()))
+        });
+    });
+}
+
+#[bench]
+#[ignore]
+fn bench_shrink_diff_small_packets(bencher: &mut Bencher) {
+    let mut rng = rand::thread_rng();
+
+    let batches = to_packet_batches(
+        &(0..NUM_PACKETS)
+            .map(|_| test_packet_with_size(128, &mut rng))
+            .collect::<Vec<_>>(),
+        PACKETS_PER_BATCH,
+    );
+
+    do_bench_shrink_packets(bencher, batches);
+}
+
+#[bench]
+#[ignore]
+fn bench_shrink_diff_big_packets(bencher: &mut Bencher) {
+    let mut rng = rand::thread_rng();
+
+    let batches = to_packet_batches(
+        &(0..NUM_PACKETS)
+            .map(|_| test_packet_with_size(1024, &mut rng))
+            .collect::<Vec<_>>(),
+        PACKETS_PER_BATCH,
+    );
+
+    do_bench_shrink_packets(bencher, batches);
+}
+
+#[bench]
+#[ignore]
+fn bench_shrink_count_packets(bencher: &mut Bencher) {
+    let mut rng = rand::thread_rng();
+
+    let mut batches = to_packet_batches(
+        &(0..NUM_PACKETS)
+            .map(|_| test_packet_with_size(128, &mut rng))
+            .collect::<Vec<_>>(),
+        PACKETS_PER_BATCH,
+    );
+    batches.iter_mut().for_each(|b| {
+        b.packets
+            .iter_mut()
+            .for_each(|p| p.meta.set_discard(thread_rng().gen()))
+    });
+
+    bencher.iter(|| {
+        let _ = sigverify::count_valid_packets(&batches);
+    });
+}