Measure batchiness

src/core/ext/transport/chttp2/transport/writing.c

@@ -168,6 +168,13 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
     grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t) {
   grpc_chttp2_stream *s;
 
+  /* stats histogram counters: we increment these throughout this function,
+     and at the end publish to the central stats histograms */
+  int flow_control_writes = 0;
+  int initial_metadata_writes = 0;
+  int trailing_metadata_writes = 0;
+  int message_writes = 0;
+
   GRPC_STATS_INC_HTTP2_WRITES_BEGUN(exec_ctx);
 
   GPR_TIMER_BEGIN("grpc_chttp2_begin_write", 0);
@@ -181,6 +188,7 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
     t->force_send_settings = 0;
     t->dirtied_local_settings = 0;
     t->sent_local_settings = 1;
+    GRPC_STATS_INC_HTTP2_SETTINGS_WRITES(exec_ctx);
   }
 
   /* simple writes are queued to qbuf, and flushed here */
@@ -257,6 +265,7 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
               gpr_inf_past(GPR_CLOCK_MONOTONIC);
           t->ping_recv_state.ping_strikes = 0;
         }
+        initial_metadata_writes++;
       } else {
         GRPC_CHTTP2_IF_TRACING(
             gpr_log(GPR_INFO, "not sending initial_metadata (Trailers-Only)"));
@@ -272,6 +281,7 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
               [num_extra_headers_for_trailing_metadata++] =
                   &s->send_initial_metadata->idx.named.content_type->md;
         }
+        trailing_metadata_writes++;
       }
       s->send_initial_metadata = NULL;
       s->sent_initial_metadata = true;
@@ -295,6 +305,7 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
             gpr_inf_past(GPR_CLOCK_MONOTONIC);
         t->ping_recv_state.ping_strikes = 0;
       }
+      flow_control_writes++;
     }
     if (sent_initial_metadata) {
       /* send any body bytes, if allowed by flow control */
@@ -393,6 +404,7 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
             GRPC_CHTTP2_STREAM_REF(s, "chttp2_writing:fork");
             grpc_chttp2_list_add_writable_stream(t, s);
           }
+          message_writes++;
         } else if (t->flow_control.remote_window == 0) {
           grpc_chttp2_list_add_stalled_by_transport(t, s);
           now_writing = true;
@@ -428,6 +440,7 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
                                     num_extra_headers_for_trailing_metadata,
                                     s->send_trailing_metadata, &hopt,
                                     &t->outbuf);
+          trailing_metadata_writes++;
         }
         s->send_trailing_metadata = NULL;
         s->sent_trailing_metadata = true;
@@ -445,6 +458,14 @@ grpc_chttp2_begin_write_result grpc_chttp2_begin_write(
     }
 
     if (now_writing) {
+      GRPC_STATS_INC_HTTP2_SEND_INITIAL_METADATA_PER_WRITE(
+          exec_ctx, initial_metadata_writes);
+      GRPC_STATS_INC_HTTP2_SEND_MESSAGE_PER_WRITE(exec_ctx, message_writes);
+      GRPC_STATS_INC_HTTP2_SEND_TRAILING_METADATA_PER_WRITE(
+          exec_ctx, trailing_metadata_writes);
+      GRPC_STATS_INC_HTTP2_SEND_FLOWCTL_PER_WRITE(exec_ctx,
+                                                  flow_control_writes);
+
       if (!grpc_chttp2_list_add_writing_stream(t, s)) {
         /* already in writing list: drop ref */
         GRPC_CHTTP2_STREAM_UNREF(exec_ctx, s, "chttp2_writing:already_writing");

src/core/lib/debug/stats_data.c

@@ -40,6 +40,7 @@ const char *grpc_stats_counter_name[GRPC_STATS_COUNTER_COUNT] = {
     "http2_op_recv_initial_metadata",
     "http2_op_recv_message",
     "http2_op_recv_trailing_metadata",
+    "http2_settings_writes",
     "http2_pings_sent",
     "http2_writes_begun",
     "http2_writes_offloaded",
@@ -76,7 +77,8 @@ const char *grpc_stats_counter_doc[GRPC_STATS_COUNTER_COUNT] = {
     "Number of batches containing receive initial metadata",
     "Number of batches containing receive message",
     "Number of batches containing receive trailing metadata",
-    "Number of HTTP2 pings sent by process", "Number of HTTP2 writes initiated",
+    "Number of settings frames sent", "Number of HTTP2 pings sent by process",
+    "Number of HTTP2 writes initiated",
     "Number of HTTP2 writes offloaded to the executor from application threads",
     "Number of HTTP2 writes that finished seeing more data needed to be "
     "written",
@@ -98,8 +100,16 @@ const char *grpc_stats_counter_doc[GRPC_STATS_COUNTER_COUNT] = {
     "the executor",
 };
 const char *grpc_stats_histogram_name[GRPC_STATS_HISTOGRAM_COUNT] = {
-    "tcp_write_size", "tcp_write_iov_size",      "tcp_read_size",
-    "tcp_read_offer", "tcp_read_offer_iov_size", "http2_send_message_size",
+    "tcp_write_size",
+    "tcp_write_iov_size",
+    "tcp_read_size",
+    "tcp_read_offer",
+    "tcp_read_offer_iov_size",
+    "http2_send_message_size",
+    "http2_send_initial_metadata_per_write",
+    "http2_send_message_per_write",
+    "http2_send_trailing_metadata_per_write",
+    "http2_send_flowctl_per_write",
 };
 const char *grpc_stats_histogram_doc[GRPC_STATS_HISTOGRAM_COUNT] = {
     "Number of bytes offered to each syscall_write",
@@ -108,6 +118,10 @@ const char *grpc_stats_histogram_doc[GRPC_STATS_HISTOGRAM_COUNT] = {
     "Number of bytes offered to each syscall_read",
     "Number of byte segments offered to each syscall_read",
     "Size of messages received by HTTP2 transport",
+    "Number of streams initiated written per TCP write",
+    "Number of streams whose payload was written per TCP write",
+    "Number of streams terminated per TCP write",
+    "Number of flow control updates written per TCP write",
 };
 const int grpc_stats_table_0[65] = {
     0,       1,       2,       3,       4,       6,       8,        11,
@@ -292,15 +306,135 @@ void grpc_stats_inc_http2_send_message_size(grpc_exec_ctx *exec_ctx,
                            grpc_stats_histo_find_bucket_slow(
                                (exec_ctx), value, grpc_stats_table_0, 64));
 }
-const int grpc_stats_histo_buckets[6] = {64, 64, 64, 64, 64, 64};
-const int grpc_stats_histo_start[6] = {0, 64, 128, 192, 256, 320};
-const int *const grpc_stats_histo_bucket_boundaries[6] = {
+void grpc_stats_inc_http2_send_initial_metadata_per_write(
+    grpc_exec_ctx *exec_ctx, int value) {
+  value = GPR_CLAMP(value, 0, 1024);
+  if (value < 13) {
+    GRPC_STATS_INC_HISTOGRAM(
+        (exec_ctx), GRPC_STATS_HISTOGRAM_HTTP2_SEND_INITIAL_METADATA_PER_WRITE,
+        value);
+    return;
+  }
+  union {
+    double dbl;
+    uint64_t uint;
+  } _val, _bkt;
+  _val.dbl = value;
+  if (_val.uint < 4637863191261478912ull) {
+    int bucket =
+        grpc_stats_table_3[((_val.uint - 4623507967449235456ull) >> 48)] + 13;
+    _bkt.dbl = grpc_stats_table_2[bucket];
+    bucket -= (_val.uint < _bkt.uint);
+    GRPC_STATS_INC_HISTOGRAM(
+        (exec_ctx), GRPC_STATS_HISTOGRAM_HTTP2_SEND_INITIAL_METADATA_PER_WRITE,
+        bucket);
+    return;
+  }
+  GRPC_STATS_INC_HISTOGRAM(
+      (exec_ctx), GRPC_STATS_HISTOGRAM_HTTP2_SEND_INITIAL_METADATA_PER_WRITE,
+      grpc_stats_histo_find_bucket_slow((exec_ctx), value, grpc_stats_table_2,
+                                        64));
+}
+void grpc_stats_inc_http2_send_message_per_write(grpc_exec_ctx *exec_ctx,
+                                                 int value) {
+  value = GPR_CLAMP(value, 0, 1024);
+  if (value < 13) {
+    GRPC_STATS_INC_HISTOGRAM(
+        (exec_ctx), GRPC_STATS_HISTOGRAM_HTTP2_SEND_MESSAGE_PER_WRITE, value);
+    return;
+  }
+  union {
+    double dbl;
+    uint64_t uint;
+  } _val, _bkt;
+  _val.dbl = value;
+  if (_val.uint < 4637863191261478912ull) {
+    int bucket =
+        grpc_stats_table_3[((_val.uint - 4623507967449235456ull) >> 48)] + 13;
+    _bkt.dbl = grpc_stats_table_2[bucket];
+    bucket -= (_val.uint < _bkt.uint);
+    GRPC_STATS_INC_HISTOGRAM(
+        (exec_ctx), GRPC_STATS_HISTOGRAM_HTTP2_SEND_MESSAGE_PER_WRITE, bucket);
+    return;
+  }
+  GRPC_STATS_INC_HISTOGRAM((exec_ctx),
+                           GRPC_STATS_HISTOGRAM_HTTP2_SEND_MESSAGE_PER_WRITE,
+                           grpc_stats_histo_find_bucket_slow(
+                               (exec_ctx), value, grpc_stats_table_2, 64));
+}
+void grpc_stats_inc_http2_send_trailing_metadata_per_write(
+    grpc_exec_ctx *exec_ctx, int value) {
+  value = GPR_CLAMP(value, 0, 1024);
+  if (value < 13) {
+    GRPC_STATS_INC_HISTOGRAM(
+        (exec_ctx), GRPC_STATS_HISTOGRAM_HTTP2_SEND_TRAILING_METADATA_PER_WRITE,
+        value);
+    return;
+  }
+  union {
+    double dbl;
+    uint64_t uint;
+  } _val, _bkt;
+  _val.dbl = value;
+  if (_val.uint < 4637863191261478912ull) {
+    int bucket =
+        grpc_stats_table_3[((_val.uint - 4623507967449235456ull) >> 48)] + 13;
+    _bkt.dbl = grpc_stats_table_2[bucket];
+    bucket -= (_val.uint < _bkt.uint);
+    GRPC_STATS_INC_HISTOGRAM(
+        (exec_ctx), GRPC_STATS_HISTOGRAM_HTTP2_SEND_TRAILING_METADATA_PER_WRITE,
+        bucket);
+    return;
+  }
+  GRPC_STATS_INC_HISTOGRAM(
+      (exec_ctx), GRPC_STATS_HISTOGRAM_HTTP2_SEND_TRAILING_METADATA_PER_WRITE,
+      grpc_stats_histo_find_bucket_slow((exec_ctx), value, grpc_stats_table_2,
+                                        64));
+}
+void grpc_stats_inc_http2_send_flowctl_per_write(grpc_exec_ctx *exec_ctx,
+                                                 int value) {
+  value = GPR_CLAMP(value, 0, 1024);
+  if (value < 13) {
+    GRPC_STATS_INC_HISTOGRAM(
+        (exec_ctx), GRPC_STATS_HISTOGRAM_HTTP2_SEND_FLOWCTL_PER_WRITE, value);
+    return;
+  }
+  union {
+    double dbl;
+    uint64_t uint;
+  } _val, _bkt;
+  _val.dbl = value;
+  if (_val.uint < 4637863191261478912ull) {
+    int bucket =
+        grpc_stats_table_3[((_val.uint - 4623507967449235456ull) >> 48)] + 13;
+    _bkt.dbl = grpc_stats_table_2[bucket];
+    bucket -= (_val.uint < _bkt.uint);
+    GRPC_STATS_INC_HISTOGRAM(
+        (exec_ctx), GRPC_STATS_HISTOGRAM_HTTP2_SEND_FLOWCTL_PER_WRITE, bucket);
+    return;
+  }
+  GRPC_STATS_INC_HISTOGRAM((exec_ctx),
+                           GRPC_STATS_HISTOGRAM_HTTP2_SEND_FLOWCTL_PER_WRITE,
+                           grpc_stats_histo_find_bucket_slow(
+                               (exec_ctx), value, grpc_stats_table_2, 64));
+}
+const int grpc_stats_histo_buckets[10] = {64, 64, 64, 64, 64,
+                                          64, 64, 64, 64, 64};
+const int grpc_stats_histo_start[10] = {0,   64,  128, 192, 256,
+                                        320, 384, 448, 512, 576};
+const int *const grpc_stats_histo_bucket_boundaries[10] = {
+    grpc_stats_table_0, grpc_stats_table_2, grpc_stats_table_0,
     grpc_stats_table_0, grpc_stats_table_2, grpc_stats_table_0,
-    grpc_stats_table_0, grpc_stats_table_2, grpc_stats_table_0};
-void (*const grpc_stats_inc_histogram[6])(grpc_exec_ctx *exec_ctx, int x) = {
+    grpc_stats_table_2, grpc_stats_table_2, grpc_stats_table_2,
+    grpc_stats_table_2};
+void (*const grpc_stats_inc_histogram[10])(grpc_exec_ctx *exec_ctx, int x) = {
     grpc_stats_inc_tcp_write_size,
     grpc_stats_inc_tcp_write_iov_size,
     grpc_stats_inc_tcp_read_size,
     grpc_stats_inc_tcp_read_offer,
     grpc_stats_inc_tcp_read_offer_iov_size,
-    grpc_stats_inc_http2_send_message_size};
+    grpc_stats_inc_http2_send_message_size,
+    grpc_stats_inc_http2_send_initial_metadata_per_write,
+    grpc_stats_inc_http2_send_message_per_write,
+    grpc_stats_inc_http2_send_trailing_metadata_per_write,
+    grpc_stats_inc_http2_send_flowctl_per_write};

src/core/lib/debug/stats_data.h

@@ -42,6 +42,7 @@ typedef enum {
   GRPC_STATS_COUNTER_HTTP2_OP_RECV_INITIAL_METADATA,
   GRPC_STATS_COUNTER_HTTP2_OP_RECV_MESSAGE,
   GRPC_STATS_COUNTER_HTTP2_OP_RECV_TRAILING_METADATA,
+  GRPC_STATS_COUNTER_HTTP2_SETTINGS_WRITES,
   GRPC_STATS_COUNTER_HTTP2_PINGS_SENT,
   GRPC_STATS_COUNTER_HTTP2_WRITES_BEGUN,
   GRPC_STATS_COUNTER_HTTP2_WRITES_OFFLOADED,
@@ -68,6 +69,10 @@ typedef enum {
   GRPC_STATS_HISTOGRAM_TCP_READ_OFFER,
   GRPC_STATS_HISTOGRAM_TCP_READ_OFFER_IOV_SIZE,
   GRPC_STATS_HISTOGRAM_HTTP2_SEND_MESSAGE_SIZE,
+  GRPC_STATS_HISTOGRAM_HTTP2_SEND_INITIAL_METADATA_PER_WRITE,
+  GRPC_STATS_HISTOGRAM_HTTP2_SEND_MESSAGE_PER_WRITE,
+  GRPC_STATS_HISTOGRAM_HTTP2_SEND_TRAILING_METADATA_PER_WRITE,
+  GRPC_STATS_HISTOGRAM_HTTP2_SEND_FLOWCTL_PER_WRITE,
   GRPC_STATS_HISTOGRAM_COUNT
 } grpc_stats_histograms;
 extern const char *grpc_stats_histogram_name[GRPC_STATS_HISTOGRAM_COUNT];
@@ -85,7 +90,15 @@ typedef enum {
   GRPC_STATS_HISTOGRAM_TCP_READ_OFFER_IOV_SIZE_BUCKETS = 64,
   GRPC_STATS_HISTOGRAM_HTTP2_SEND_MESSAGE_SIZE_FIRST_SLOT = 320,
   GRPC_STATS_HISTOGRAM_HTTP2_SEND_MESSAGE_SIZE_BUCKETS = 64,
-  GRPC_STATS_HISTOGRAM_BUCKETS = 384
+  GRPC_STATS_HISTOGRAM_HTTP2_SEND_INITIAL_METADATA_PER_WRITE_FIRST_SLOT = 384,
+  GRPC_STATS_HISTOGRAM_HTTP2_SEND_INITIAL_METADATA_PER_WRITE_BUCKETS = 64,
+  GRPC_STATS_HISTOGRAM_HTTP2_SEND_MESSAGE_PER_WRITE_FIRST_SLOT = 448,
+  GRPC_STATS_HISTOGRAM_HTTP2_SEND_MESSAGE_PER_WRITE_BUCKETS = 64,
+  GRPC_STATS_HISTOGRAM_HTTP2_SEND_TRAILING_METADATA_PER_WRITE_FIRST_SLOT = 512,
+  GRPC_STATS_HISTOGRAM_HTTP2_SEND_TRAILING_METADATA_PER_WRITE_BUCKETS = 64,
+  GRPC_STATS_HISTOGRAM_HTTP2_SEND_FLOWCTL_PER_WRITE_FIRST_SLOT = 576,
+  GRPC_STATS_HISTOGRAM_HTTP2_SEND_FLOWCTL_PER_WRITE_BUCKETS = 64,
+  GRPC_STATS_HISTOGRAM_BUCKETS = 640
 } grpc_stats_histogram_constants;
 #define GRPC_STATS_INC_CLIENT_CALLS_CREATED(exec_ctx) \
   GRPC_STATS_INC_COUNTER((exec_ctx), GRPC_STATS_COUNTER_CLIENT_CALLS_CREATED)
@@ -126,6 +139,8 @@ typedef enum {
 #define GRPC_STATS_INC_HTTP2_OP_RECV_TRAILING_METADATA(exec_ctx) \
   GRPC_STATS_INC_COUNTER((exec_ctx),                             \
                          GRPC_STATS_COUNTER_HTTP2_OP_RECV_TRAILING_METADATA)
+#define GRPC_STATS_INC_HTTP2_SETTINGS_WRITES(exec_ctx) \
+  GRPC_STATS_INC_COUNTER((exec_ctx), GRPC_STATS_COUNTER_HTTP2_SETTINGS_WRITES)
 #define GRPC_STATS_INC_HTTP2_PINGS_SENT(exec_ctx) \
   GRPC_STATS_INC_COUNTER((exec_ctx), GRPC_STATS_COUNTER_HTTP2_PINGS_SENT)
 #define GRPC_STATS_INC_HTTP2_WRITES_BEGUN(exec_ctx) \
@@ -182,10 +197,27 @@ void grpc_stats_inc_tcp_read_offer_iov_size(grpc_exec_ctx *exec_ctx, int x);
 #define GRPC_STATS_INC_HTTP2_SEND_MESSAGE_SIZE(exec_ctx, value) \
   grpc_stats_inc_http2_send_message_size((exec_ctx), (int)(value))
 void grpc_stats_inc_http2_send_message_size(grpc_exec_ctx *exec_ctx, int x);
-extern const int grpc_stats_histo_buckets[6];
-extern const int grpc_stats_histo_start[6];
-extern const int *const grpc_stats_histo_bucket_boundaries[6];
-extern void (*const grpc_stats_inc_histogram[6])(grpc_exec_ctx *exec_ctx,
+#define GRPC_STATS_INC_HTTP2_SEND_INITIAL_METADATA_PER_WRITE(exec_ctx, value) \
+  grpc_stats_inc_http2_send_initial_metadata_per_write((exec_ctx), (int)(value))
+void grpc_stats_inc_http2_send_initial_metadata_per_write(
+    grpc_exec_ctx *exec_ctx, int x);
+#define GRPC_STATS_INC_HTTP2_SEND_MESSAGE_PER_WRITE(exec_ctx, value) \
+  grpc_stats_inc_http2_send_message_per_write((exec_ctx), (int)(value))
+void grpc_stats_inc_http2_send_message_per_write(grpc_exec_ctx *exec_ctx,
                                                  int x);
+#define GRPC_STATS_INC_HTTP2_SEND_TRAILING_METADATA_PER_WRITE(exec_ctx, value) \
+  grpc_stats_inc_http2_send_trailing_metadata_per_write((exec_ctx),            \
+                                                        (int)(value))
+void grpc_stats_inc_http2_send_trailing_metadata_per_write(
+    grpc_exec_ctx *exec_ctx, int x);
+#define GRPC_STATS_INC_HTTP2_SEND_FLOWCTL_PER_WRITE(exec_ctx, value) \
+  grpc_stats_inc_http2_send_flowctl_per_write((exec_ctx), (int)(value))
+void grpc_stats_inc_http2_send_flowctl_per_write(grpc_exec_ctx *exec_ctx,
+                                                 int x);
+extern const int grpc_stats_histo_buckets[10];
+extern const int grpc_stats_histo_start[10];
+extern const int *const grpc_stats_histo_bucket_boundaries[10];
+extern void (*const grpc_stats_inc_histogram[10])(grpc_exec_ctx *exec_ctx,
+                                                  int x);
 
 #endif /* GRPC_CORE_LIB_DEBUG_STATS_DATA_H */

src/core/lib/debug/stats_data.yaml

@@ -79,6 +79,24 @@
   max: 16777216
   buckets: 64
   doc: Size of messages received by HTTP2 transport
+- histogram: http2_send_initial_metadata_per_write
+  max: 1024
+  buckets: 64
+  doc: Number of streams initiated written per TCP write
+- histogram: http2_send_message_per_write
+  max: 1024
+  buckets: 64
+  doc: Number of streams whose payload was written per TCP write
+- histogram: http2_send_trailing_metadata_per_write
+  max: 1024
+  buckets: 64
+  doc: Number of streams terminated per TCP write
+- histogram: http2_send_flowctl_per_write
+  max: 1024
+  buckets: 64
+  doc: Number of flow control updates written per TCP write
+- counter: http2_settings_writes
+  doc: Number of settings frames sent
 - counter: http2_pings_sent
   doc: Number of HTTP2 pings sent by process
 - counter: http2_writes_begun