diff --git a/src/FwdState.cc b/src/FwdState.cc
index f16acd0..c1d8a0f 100644
--- a/src/FwdState.cc
+++ b/src/FwdState.cc
@@ -139,7 +139,6 @@ FwdState::FwdState(const Comm::ConnectionPointer &client, StoreEntry * e, HttpRe
start_t = squid_curtime;
serverDestinations.reserve(Config.forward_max_tries);
e->lock("FwdState");
- EBIT_SET(e->flags, ENTRY_FWD_HDR_WAIT);
}
// Called once, right after object creation, when it is safe to set self
@@ -250,7 +249,6 @@ FwdState::completed()
}
#endif
} else {
- EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
entry->complete();
entry->releaseRequest();
}
@@ -495,7 +493,6 @@ FwdState::complete()
debugs(17, 3, HERE << "server FD " << serverConnection()->fd << " not re-forwarding status " << entry->getReply()->sline.status());
else
debugs(17, 3, HERE << "server (FD closed) not re-forwarding status " << entry->getReply()->sline.status());
- EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
entry->complete();
if (!Comm::IsConnOpen(serverConn))
diff --git a/src/MemStore.cc b/src/MemStore.cc
index 86b6024..405b644 100644
--- a/src/MemStore.cc
+++ b/src/MemStore.cc
@@ -402,7 +402,6 @@ MemStore::copyFromShmSlice(StoreEntry &e, const StoreIOBuffer &buf, bool eof)
const int result = rep->httpMsgParseStep(mb.buf, buf.length, eof);
if (result > 0) {
assert(rep->pstate == psParsed);
- EBIT_CLR(e.flags, ENTRY_FWD_HDR_WAIT);
} else if (result < 0) {
debugs(20, DBG_IMPORTANT, "Corrupted mem-cached headers: " << e);
return false;
@@ -508,15 +507,9 @@ MemStore::startCaching(StoreEntry &e)
void
MemStore::copyToShm(StoreEntry &e)
{
- // prevents remote readers from getting ENTRY_FWD_HDR_WAIT entries and
- // not knowing when the wait is over
- if (EBIT_TEST(e.flags, ENTRY_FWD_HDR_WAIT)) {
- debugs(20, 5, "postponing copying " << e << " for ENTRY_FWD_HDR_WAIT");
- return;
- }
-
assert(map);
assert(e.mem_obj);
+ Must(!EBIT_TEST(e.flags, ENTRY_FWD_HDR_WAIT));
const int32_t index = e.mem_obj->memCache.index;
assert(index >= 0);
diff --git a/src/client_side_request.cc b/src/client_side_request.cc
index a824b08..5debc29 100644
--- a/src/client_side_request.cc
+++ b/src/client_side_request.cc
@@ -1919,7 +1919,6 @@ ClientHttpRequest::handleAdaptedHeader(HttpMsg *msg)
assert(repContext);
repContext->createStoreEntry(request->method, request->flags);
- EBIT_CLR(storeEntry()->flags, ENTRY_FWD_HDR_WAIT);
request_satisfaction_mode = true;
request_satisfaction_offset = 0;
storeEntry()->replaceHttpReply(new_rep);
diff --git a/src/clients/FtpGateway.cc b/src/clients/FtpGateway.cc
index 9c78bbb..4f8319a 100644
--- a/src/clients/FtpGateway.cc
+++ b/src/clients/FtpGateway.cc
@@ -2309,7 +2309,6 @@ Ftp::Gateway::completedListing()
ferr.ftp.server_msg = ctrl.message;
ctrl.message = NULL;
entry->replaceHttpReply( ferr.BuildHttpReply() );
- EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
entry->flush();
entry->unlock("Ftp::Gateway");
}
@@ -2588,8 +2587,6 @@ Ftp::Gateway::appendSuccessHeader()
assert(entry->isEmpty());
- EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
-
entry->buffer(); /* released when done processing current data payload */
filename = (t = urlpath.rpos('/')) ? t + 1 : urlpath.termedBuf();
diff --git a/src/clients/FtpRelay.cc b/src/clients/FtpRelay.cc
index ed498b4..f1d4e9e 100644
--- a/src/clients/FtpRelay.cc
+++ b/src/clients/FtpRelay.cc
@@ -290,7 +290,6 @@ Ftp::Relay::failedErrorMessage(err_type error, int xerrno)
const Http::StatusCode httpStatus = failedHttpStatus(error);
HttpReply *const reply = createHttpReply(httpStatus);
entry->replaceHttpReply(reply);
- EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
fwd->request->detailError(error, xerrno);
}
@@ -373,7 +372,6 @@ void
Ftp::Relay::forwardReply()
{
assert(entry->isEmpty());
- EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
HttpReply *const reply = createHttpReply(Http::scNoContent);
@@ -448,7 +446,6 @@ Ftp::Relay::startDataDownload()
" (" << data.conn->local << ")");
HttpReply *const reply = createHttpReply(Http::scOkay, -1);
- EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
setVirginReply(reply);
adaptOrFinalizeReply();
diff --git a/src/enums.h b/src/enums.h
index 4d04805..50199da 100644
--- a/src/enums.h
+++ b/src/enums.h
@@ -96,12 +96,31 @@ typedef enum {
enum {
ENTRY_SPECIAL,
ENTRY_REVALIDATE,
+
+ /// Tiny Store writes are likely. The writes should be aggregated together
+ /// before Squid announces the new content availability to the store
+ /// clients. For example, forming a cached HTTP response header may result
+ /// in dozens of StoreEntry::write() calls, many of which adding as little
+ /// as two bytes. Sharing those small writes with the store clients
+ /// increases overhead, especially because the client code can do nothing
+ /// useful with the written content until the whole response header is
+ /// stored. Might be combined with ENTRY_FWD_HDR_WAIT. TODO: Rename to
+ /// ENTRY_DELAY_WHILE_COALESCING to emphasize the difference from and
+ /// similarity with ENTRY_FWD_HDR_WAIT.
DELAY_SENDING,
RELEASE_REQUEST,
REFRESH_REQUEST,
ENTRY_CACHABLE_RESERVED_FOR_FUTURE_USE,
ENTRY_DISPATCHED,
KEY_PRIVATE,
+
+ /// The current entry response may change. The contents of an entry in this
+ /// state must not be shared with its store clients. For example, Squid
+ /// receives (and buffers) an HTTP/504 response but may decide to retry that
+ /// transaction to receive a successful response from another server
+ /// instead. Might be combined with DELAY_SENDING. TODO: Rename to
+ /// ENTRY_DELAY_WHILE_WOBBLING to emphasize the difference from and
+ /// similarity with DELAY_SENDING.
ENTRY_FWD_HDR_WAIT,
ENTRY_NEGCACHED,
ENTRY_VALIDATED,
diff --git a/src/gopher.cc b/src/gopher.cc
index d373e8a..6d4ab1e 100644
--- a/src/gopher.cc
+++ b/src/gopher.cc
@@ -233,7 +233,6 @@ gopherMimeCreate(GopherStateData * gopherState)
}
assert(entry->isEmpty());
- EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
HttpReply *reply = new HttpReply;
entry->buffer();
diff --git a/src/http.cc b/src/http.cc
index 1dd1e6d..08531dc 100644
--- a/src/http.cc
+++ b/src/http.cc
@@ -932,8 +932,8 @@ HttpStateData::haveParsedReplyHeaders()
if (vary.isEmpty()) {
entry->makePrivate();
- if (!fwd->reforwardableStatus(rep->sline.status()))
- EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
+ if (fwd->reforwardableStatus(rep->sline.status()))
+ EBIT_SET(entry->flags, ENTRY_FWD_HDR_WAIT);
varyFailure = true;
} else {
entry->mem_obj->vary_headers = vary;
@@ -945,8 +945,8 @@ HttpStateData::haveParsedReplyHeaders()
* If its not a reply that we will re-forward, then
* allow the client to get it.
*/
- if (!fwd->reforwardableStatus(rep->sline.status()))
- EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
+ if (fwd->reforwardableStatus(rep->sline.status()))
+ EBIT_SET(entry->flags, ENTRY_FWD_HDR_WAIT);
switch (cacheableReply()) {
diff --git a/src/ipc/Forwarder.cc b/src/ipc/Forwarder.cc
index bf3c428..116d6f0 100644
--- a/src/ipc/Forwarder.cc
+++ b/src/ipc/Forwarder.cc
@@ -94,8 +94,10 @@ Ipc::Forwarder::handleRemoteAck()
{
debugs(54, 3, HERE);
request->requestId = 0;
- // Do not clear ENTRY_FWD_HDR_WAIT or do entry->complete() because
- // it will trigger our client side processing. Let job cleanup close.
+ // Do not do entry->complete() because it will trigger our client side
+ // processing when we no longer own the client-Squid connection.
+ // Let job cleanup close the client-Squid connection that Coordinator
+ // now owns.
}
/// Ipc::Forwarder::requestTimedOut wrapper
diff --git a/src/mgr/Forwarder.cc b/src/mgr/Forwarder.cc
index 3c4e4f3..7d33a9b 100644
--- a/src/mgr/Forwarder.cc
+++ b/src/mgr/Forwarder.cc
@@ -37,7 +37,6 @@ Mgr::Forwarder::Forwarder(const Comm::ConnectionPointer &aConn, const ActionPara
HTTPMSGLOCK(httpRequest);
entry->lock("Mgr::Forwarder");
- EBIT_SET(entry->flags, ENTRY_FWD_HDR_WAIT);
closer = asyncCall(16, 5, "Mgr::Forwarder::noteCommClosed",
CommCbMemFunT<Forwarder, CommCloseCbParams>(this, &Forwarder::noteCommClosed));
@@ -122,7 +121,6 @@ Mgr::Forwarder::sendError(ErrorState *error)
Must(entry != NULL);
Must(httpRequest != NULL);
- EBIT_CLR(entry->flags, ENTRY_FWD_HDR_WAIT);
entry->buffer();
entry->replaceHttpReply(error->BuildHttpReply());
entry->expires = squid_curtime;
diff --git a/src/store.cc b/src/store.cc
index cbb2676..c5ae817 100644
--- a/src/store.cc
+++ b/src/store.cc
@@ -831,8 +831,12 @@ StoreEntry::write (StoreIOBuffer writeBuffer)
storeGetMemSpace(writeBuffer.length);
mem_obj->write(writeBuffer);
- if (!EBIT_TEST(flags, DELAY_SENDING))
- invokeHandlers();
+ if (EBIT_TEST(flags, ENTRY_FWD_HDR_WAIT) && !mem_obj->readAheadPolicyCanRead()) {
+ debugs(20, 3, "allow Store clients to get entry content after buffering too much for " << *this);
+ EBIT_CLR(flags, ENTRY_FWD_HDR_WAIT);
+ }
+
+ invokeHandlers();
}
/* Append incoming data from a primary server to an entry. */
@@ -1047,6 +1051,9 @@ StoreEntry::complete()
{
debugs(20, 3, "storeComplete: '" << getMD5Text() << "'");
+ // To preserve forwarding retries, call FwdState::complete() instead.
+ EBIT_CLR(flags, ENTRY_FWD_HDR_WAIT);
+
if (store_status != STORE_PENDING) {
/*
* if we're not STORE_PENDING, then probably we got aborted
@@ -1103,6 +1110,9 @@ StoreEntry::abort()
EBIT_SET(flags, ENTRY_ABORTED);
+ // allow the Store clients to be told about the problem
+ EBIT_CLR(flags, ENTRY_FWD_HDR_WAIT);
+
setMemStatus(NOT_IN_MEMORY);
store_status = STORE_OK;
@@ -1890,7 +1900,6 @@ StoreEntry::startWriting()
rep->packHeadersInto(&p);
mem_obj->markEndOfReplyHeaders();
- EBIT_CLR(flags, ENTRY_FWD_HDR_WAIT);
rep->body.packInto(&p);
diff --git a/src/store_client.cc b/src/store_client.cc
index 07a05d4..7ee1b10 100644
--- a/src/store_client.cc
+++ b/src/store_client.cc
@@ -282,11 +282,6 @@ storeClientCopy2(StoreEntry * e, store_client * sc)
return;
}
- if (EBIT_TEST(e->flags, ENTRY_FWD_HDR_WAIT)) {
- debugs(90, 5, "storeClientCopy2: returning because ENTRY_FWD_HDR_WAIT set");
- return;
- }
-
if (sc->flags.store_copying) {
sc->flags.copy_event_pending = true;
debugs(90, 3, "storeClientCopy2: Queueing storeClientCopyEvent()");
@@ -720,6 +715,15 @@ storeUnregister(store_client * sc, StoreEntry * e, void *data)
void
StoreEntry::invokeHandlers()
{
+ if (EBIT_TEST(flags, DELAY_SENDING)) {
+ debugs(90, 3, "DELAY_SENDING is on, exiting " << *this);
+ return;
+ }
+ if (EBIT_TEST(flags, ENTRY_FWD_HDR_WAIT)) {
+ debugs(90, 3, "ENTRY_FWD_HDR_WAIT is on, exiting " << *this);
+ return;
+ }
+
/* Commit what we can to disk, if appropriate */
swapOut();
int i = 0;