shrink batches when over 80% of the space is wasted (backport #23066) (#23189)

* shrink batches when over 80% of the space is wasted (#23066)

* shrink batches when over 80% of the space is wasted

(cherry picked from commit 83d31c9e65)

# Conflicts:
#	core/benches/sigverify_stage.rs
#	core/src/sigverify_stage.rs
#	perf/src/sigverify.rs

* fixup!

Co-authored-by: anatoly yakovenko <anatoly@solana.com>

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::{
@@ -59,6 +59,9 @@ 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 {
@@ -167,6 +170,9 @@ 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),
         );
     }
 }
@@ -242,7 +248,20 @@ impl SigVerifyStage {
         discard_time.stop();
 
         let mut verify_batch_time = Measure::start("sigverify_batch_time");
-        let batches = verifier.verify_batches(batches);
+        let mut batches = verifier.verify_batches(batches);
+        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();
 
@@ -276,7 +295,10 @@ 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(())
     }
@@ -342,6 +364,12 @@ 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 std::sync::mpsc::channel;
     use {super::*, solana_perf::packet::Packet};
 
     fn count_non_discard(packet_batches: &[PacketBatch]) -> usize {
@@ -370,4 +398,58 @@ mod tests {
         assert!(!batches[0].packets[0].meta.discard());
         assert!(!batches[0].packets[3].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) = channel();
+        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();
+    }
 }