Release 1.17.15

- [BUGFIX] http_client: make sure only one read per on_read() callback is performed in the header conversion bypass (-B) mode. - http_client: with -E, assign random priority when stream is created. - [OPTIMIZATION] On immediate write, place an ACK frame into the first buffered packet if an ACK is queued. This reduces the number of standalone ACK packets. - [OPTIMIZATION] Allow placing more than one STREAM frame from the same stream into an outgoing packet. This change minimizes the number of buffered packets required to store several small HTTP messages by virtue of allowing more than one STREAM frame from HEADERS stream in the same packet. - [OPTIMIZATION] Flush headers when writing to buffered packets. This causes the headers to be written to the same buffered packet queue, thereby improving packet utilization, especially for small HTTP messages.
litespeedtech · Jan 21, 2019 · 4d83f5b · 4d83f5b
1 parent 046163b
commit 4d83f5b
Show file tree

Hide file tree

Showing 14 changed files with 400 additions and 240 deletions.
diff --git a/CHANGELOG b/CHANGELOG
@@ -1,3 +1,21 @@
+2019-01-17
+    - 1.17.15
+    - [BUGFIX] http_client: make sure only one read per on_read() callback
+      is performed in the header conversion bypass (-B) mode.
+    - http_client: with -E, assign random priority when stream is created.
+    - [OPTIMIZATION] On immediate write, place an ACK frame into the first
+      buffered packet if an ACK is queued.  This reduces the number of
+      standalone ACK packets.
+    - [OPTIMIZATION] Allow placing more than one STREAM frame from the same
+      stream into an outgoing packet.  This change minimizes the number of
+      buffered packets required to store several small HTTP messages by
+      virtue of allowing more than one STREAM frame from HEADERS stream in
+      the same packet.
+    - [OPTIMIZATION] Flush headers when writing to buffered packets.  This
+      causes the headers to be written to the same buffered packet queue,
+      thereby improving packet utilization, especially for small HTTP
+      messages.
+
 2019-01-16
     - 1.17.14
     - [FEATURE] http_client can now collect stats: time to connect, TTFB,

diff --git a/include/lsquic.h b/include/lsquic.h
@@ -25,7 +25,7 @@ extern "C" {
 
 #define LSQUIC_MAJOR_VERSION 1
 #define LSQUIC_MINOR_VERSION 17
-#define LSQUIC_PATCH_VERSION 14
+#define LSQUIC_PATCH_VERSION 15
 
 /**
  * Engine flags:

diff --git a/src/liblsquic/lsquic_conn.h b/src/liblsquic/lsquic_conn.h
@@ -87,6 +87,13 @@ struct conn_iface
     lsquic_time_t
     (*ci_next_tick_time) (struct lsquic_conn *);
 
+    int
+    (*ci_can_write_ack) (struct lsquic_conn *);
+
+    /* No return status: best effort */
+    void
+    (*ci_write_ack) (struct lsquic_conn *, struct lsquic_packet_out *);
+
 #if LSQUIC_CONN_STATS
     const struct conn_stats *
     (*ci_get_stats) (struct lsquic_conn *);

diff --git a/src/liblsquic/lsquic_full_conn.c b/src/liblsquic/lsquic_full_conn.c
@@ -903,6 +903,93 @@ reset_ack_state (struct full_conn *conn)
 }
 
 
+#if 1
+#   define verify_ack_frame(a, b, c)
+#else
+static void
+verify_ack_frame (struct full_conn *conn, const unsigned char *buf, int bufsz)
+{
+    unsigned i;
+    int parsed_len;
+    struct ack_info *ack_info;
+    const struct lsquic_packno_range *range;
+    char ack_buf[512];
+    unsigned buf_off = 0;
+    int nw;
+
+    ack_info = conn->fc_pub.mm->acki;
+    parsed_len = parse_ack_frame(buf, bufsz, ack_info);
+    assert(parsed_len == bufsz);
+
+    for (range = lsquic_rechist_first(&conn->fc_rechist), i = 0; range;
+            range = lsquic_rechist_next(&conn->fc_rechist), ++i)
+    {
+        assert(i < ack_info->n_ranges);
+        assert(range->high == ack_info->ranges[i].high);
+        assert(range->low == ack_info->ranges[i].low);
+        if (LSQ_LOG_ENABLED(LSQ_LOG_DEBUG))
+        {
+            nw = snprintf(ack_buf + buf_off, sizeof(ack_buf) - buf_off,
+                            "[%"PRIu64"-%"PRIu64"]", range->high, range->low);
+            assert(nw >= 0);
+            buf_off += nw;
+        }
+    }
+    assert(i == ack_info->n_ranges);
+    LSQ_DEBUG("Sent ACK frame %s", ack_buf);
+}
+
+
+#endif
+
+
+static void
+full_conn_ci_write_ack (struct lsquic_conn *lconn,
+                                    struct lsquic_packet_out *packet_out)
+{
+    struct full_conn *conn = (struct full_conn *) lconn;
+    lsquic_time_t now;
+    int has_missing, w;
+
+    now = lsquic_time_now();
+    w = conn->fc_conn.cn_pf->pf_gen_ack_frame(
+            packet_out->po_data + packet_out->po_data_sz,
+            lsquic_packet_out_avail(packet_out),
+            (gaf_rechist_first_f)        lsquic_rechist_first,
+            (gaf_rechist_next_f)         lsquic_rechist_next,
+            (gaf_rechist_largest_recv_f) lsquic_rechist_largest_recv,
+            &conn->fc_rechist, now, &has_missing, &packet_out->po_ack2ed);
+    if (w < 0) {
+        ABORT_ERROR("generating ACK frame failed: %d", errno);
+        return;
+    }
+#if LSQUIC_CONN_STATS
+    ++conn->fc_stats.out.acks;
+#endif
+    EV_LOG_GENERATED_ACK_FRAME(LSQUIC_LOG_CONN_ID, conn->fc_conn.cn_pf,
+                        packet_out->po_data + packet_out->po_data_sz, w);
+    verify_ack_frame(conn, packet_out->po_data + packet_out->po_data_sz, w);
+    lsquic_send_ctl_scheduled_ack(&conn->fc_send_ctl);
+    packet_out->po_frame_types |= 1 << QUIC_FRAME_ACK;
+    lsquic_send_ctl_incr_pack_sz(&conn->fc_send_ctl, packet_out, w);
+    packet_out->po_regen_sz += w;
+    if (has_missing)
+        conn->fc_flags |= FC_ACK_HAD_MISS;
+    else
+        conn->fc_flags &= ~FC_ACK_HAD_MISS;
+    LSQ_DEBUG("Put %d bytes of ACK frame into packet on outgoing queue", w);
+    if (conn->fc_conn.cn_version >= LSQVER_039 &&
+            conn->fc_n_cons_unretx >= 20 &&
+                !lsquic_send_ctl_have_outgoing_retx_frames(&conn->fc_send_ctl))
+    {
+        LSQ_DEBUG("schedule WINDOW_UPDATE frame after %u non-retx "
+                                    "packets sent", conn->fc_n_cons_unretx);
+        conn->fc_flags |= FC_SEND_WUF;
+    }
+    reset_ack_state(conn);
+}
+
+
 static lsquic_stream_t *
 new_stream_ext (struct full_conn *conn, uint32_t stream_id, int if_idx,
                 enum stream_ctor_flags stream_ctor_flags)
@@ -2232,7 +2319,7 @@ generate_rst_stream_frame (struct full_conn *conn, lsquic_stream_t *stream)
     lsquic_send_ctl_incr_pack_sz(&conn->fc_send_ctl, packet_out, sz);
     packet_out->po_frame_types |= 1 << QUIC_FRAME_RST_STREAM;
     s = lsquic_packet_out_add_stream(packet_out, conn->fc_pub.mm, stream,
-                                     QUIC_FRAME_RST_STREAM, 0, 0);
+                             QUIC_FRAME_RST_STREAM, packet_out->po_data_sz, sz);
     if (s != 0)
     {
         ABORT_ERROR("adding stream to packet failed: %s", strerror(errno));
@@ -2578,96 +2665,19 @@ process_hsk_stream_write_events (struct full_conn *conn)
 }
 
 
-#if 1
-#   define verify_ack_frame(a, b, c)
-#else
-static void
-verify_ack_frame (struct full_conn *conn, const unsigned char *buf, int bufsz)
-{
-    unsigned i;
-    int parsed_len;
-    struct ack_info *ack_info;
-    const struct lsquic_packno_range *range;
-    char ack_buf[512];
-    unsigned buf_off = 0;
-    int nw;
-
-    ack_info = conn->fc_pub.mm->acki;
-    parsed_len = parse_ack_frame(buf, bufsz, ack_info);
-    assert(parsed_len == bufsz);
-
-    for (range = lsquic_rechist_first(&conn->fc_rechist), i = 0; range;
-            range = lsquic_rechist_next(&conn->fc_rechist), ++i)
-    {
-        assert(i < ack_info->n_ranges);
-        assert(range->high == ack_info->ranges[i].high);
-        assert(range->low == ack_info->ranges[i].low);
-        if (LSQ_LOG_ENABLED(LSQ_LOG_DEBUG))
-        {
-            nw = snprintf(ack_buf + buf_off, sizeof(ack_buf) - buf_off,
-                            "[%"PRIu64"-%"PRIu64"]", range->high, range->low);
-            assert(nw >= 0);
-            buf_off += nw;
-        }
-    }
-    assert(i == ack_info->n_ranges);
-    LSQ_DEBUG("Sent ACK frame %s", ack_buf);
-}
-
-
-#endif
-
-
 static void
 generate_ack_frame (struct full_conn *conn)
 {
     lsquic_packet_out_t *packet_out;
-    lsquic_time_t now;
-    int has_missing, w;
 
     packet_out = lsquic_send_ctl_new_packet_out(&conn->fc_send_ctl, 0);
-    if (!packet_out)
+    if (packet_out)
     {
-        ABORT_ERROR("cannot allocate packet: %s", strerror(errno));
-        return;
+        lsquic_send_ctl_scheduled_one(&conn->fc_send_ctl, packet_out);
+        full_conn_ci_write_ack(&conn->fc_conn, packet_out);
     }
-
-    lsquic_send_ctl_scheduled_one(&conn->fc_send_ctl, packet_out);
-    now = lsquic_time_now();
-    w = conn->fc_conn.cn_pf->pf_gen_ack_frame(
-            packet_out->po_data + packet_out->po_data_sz,
-            lsquic_packet_out_avail(packet_out),
-            (gaf_rechist_first_f)        lsquic_rechist_first,
-            (gaf_rechist_next_f)         lsquic_rechist_next,
-            (gaf_rechist_largest_recv_f) lsquic_rechist_largest_recv,
-            &conn->fc_rechist, now, &has_missing, &packet_out->po_ack2ed);
-    if (w < 0) {
-        ABORT_ERROR("generating ACK frame failed: %d", errno);
-        return;
-    }
-#if LSQUIC_CONN_STATS
-    ++conn->fc_stats.out.acks;
-#endif
-    EV_LOG_GENERATED_ACK_FRAME(LSQUIC_LOG_CONN_ID, conn->fc_conn.cn_pf,
-                        packet_out->po_data + packet_out->po_data_sz, w);
-    verify_ack_frame(conn, packet_out->po_data + packet_out->po_data_sz, w);
-    lsquic_send_ctl_scheduled_ack(&conn->fc_send_ctl);
-    packet_out->po_frame_types |= 1 << QUIC_FRAME_ACK;
-    lsquic_send_ctl_incr_pack_sz(&conn->fc_send_ctl, packet_out, w);
-    packet_out->po_regen_sz += w;
-    if (has_missing)
-        conn->fc_flags |= FC_ACK_HAD_MISS;
     else
-        conn->fc_flags &= ~FC_ACK_HAD_MISS;
-    LSQ_DEBUG("Put %d bytes of ACK frame into packet on outgoing queue", w);
-    if (conn->fc_conn.cn_version >= LSQVER_039 &&
-            conn->fc_n_cons_unretx >= 20 &&
-                !lsquic_send_ctl_have_outgoing_retx_frames(&conn->fc_send_ctl))
-    {
-        LSQ_DEBUG("schedule WINDOW_UPDATE frame after %u non-retx "
-                                    "packets sent", conn->fc_n_cons_unretx);
-        conn->fc_flags |= FC_SEND_WUF;
-    }
+        ABORT_ERROR("cannot allocate packet: %s", strerror(errno));
 }
 
 
@@ -2775,6 +2785,14 @@ should_generate_ack (const struct full_conn *conn)
 }
 
 
+static int
+full_conn_ci_can_write_ack (struct lsquic_conn *lconn)
+{
+    struct full_conn *conn = (struct full_conn *) lconn;
+    return should_generate_ack(conn);
+}
+
+
 static enum tick_st
 full_conn_ci_tick (lsquic_conn_t *lconn, lsquic_time_t now)
 {
@@ -2874,7 +2892,6 @@ full_conn_ci_tick (lsquic_conn_t *lconn, lsquic_time_t now)
          */
         generate_ack_frame(conn);
         CLOSE_IF_NECESSARY();
-        reset_ack_state(conn);
 
         /* Try to send STOP_WAITING frame at the same time we send an ACK
          * This follows reference implementation.
@@ -3575,6 +3592,7 @@ static const struct headers_stream_callbacks headers_callbacks =
 static const struct headers_stream_callbacks *headers_callbacks_ptr = &headers_callbacks;
 
 static const struct conn_iface full_conn_iface = {
+    .ci_can_write_ack        =  full_conn_ci_can_write_ack,
     .ci_destroy              =  full_conn_ci_destroy,
 #if LSQUIC_CONN_STATS
     .ci_get_stats            =  full_conn_ci_get_stats,
@@ -3588,6 +3606,7 @@ static const struct conn_iface full_conn_iface = {
     .ci_packet_not_sent      =  full_conn_ci_packet_not_sent,
     .ci_packet_sent          =  full_conn_ci_packet_sent,
     .ci_tick                 =  full_conn_ci_tick,
+    .ci_write_ack            =  full_conn_ci_write_ack,
 };
 
 static const struct conn_iface *full_conn_iface_ptr = &full_conn_iface;