configurable write session buffer limit (#14955)

Author: alexnick88

ydb/core/protos/pqconfig.proto

@@ -207,6 +207,8 @@ message TPQConfig {
 
     optional uint64 BalancerWakeupIntervalSec = 54 [default = 30];
     optional uint64 BalancerStatsWakeupIntervalSec = 55 [default = 5];
+
+    optional uint64 MaxWriteSessionBytesInflight = 57 [default = 1000000];
 }
 
 message TChannelProfile {

ydb/services/persqueue_v1/actors/write_session_actor.cpp

@@ -159,7 +159,6 @@ namespace NGRpcProxy::V1 {
 
 using namespace Ydb::PersQueue::V1;
 
-static const ui32 MAX_BYTES_INFLIGHT = 1_MB;
 static const TDuration SOURCEID_UPDATE_PERIOD = TDuration::Hours(1);
 
 // metering
@@ -942,7 +941,7 @@ void TWriteSessionActor<UseMigrationProtocol>::Handle(NPQ::TEvPartitionWriter::T
     if (BytesInflight) {
         BytesInflight.Dec(diff);
     }
-    if (!NextRequestInited && BytesInflight_ < MAX_BYTES_INFLIGHT) { //allow only one big request to be readed but not sended
+    if (!NextRequestInited && BytesInflight_ < AppData(ctx)->PQConfig.GetMaxWriteSessionBytesInflight()) { //allow only one big request to be readed but not sended
         NextRequestInited = true;
         if (!Request->GetStreamCtx()->Read()) {
             LOG_INFO_S(ctx, NKikimrServices::PQ_WRITE_PROXY, "session v1 cookie: " << Cookie << " sessionId: " << OwnerCookie << " grpc read failed");
@@ -1498,7 +1497,7 @@ void TWriteSessionActor<UseMigrationProtocol>::Handle(typename TEvWrite::TPtr& e
         BytesInflightTotal.Inc(diff);
     }
 
-    if (BytesInflight_ < MAX_BYTES_INFLIGHT) { //allow only one big request to be readed but not sended
+    if (BytesInflight_ < AppData(ctx)->PQConfig.GetMaxWriteSessionBytesInflight()) { //allow only one big request to be readed but not sended
         Y_ABORT_UNLESS(NextRequestInited);
         if (!Request->GetStreamCtx()->Read()) {
             LOG_INFO_S(ctx, NKikimrServices::PQ_WRITE_PROXY, "session v1 cookie: " << Cookie << " sessionId: " << OwnerCookie << " grpc read failed");