This commit introduces the max inflight bytes setting at the Config level, and
tests that raft flow control honours it.
Signed-off-by: Pavel Kalinnikov <pavel@cockroachlabs.com>
The Inflights type has limits on the message size and the number of inflight
messages. However, a single large entry that exceeds the size limit can still
be sent. In combination with the max messages count limit, many large messages
can be sent in a row and overflow the receiver. In effect, the "max" values act
as "target" rather than hard limits.
This commit adds an additional soft limit on the total size of inflight
messages, which catches such situations and prevents the receiver overflow.
Signed-off-by: Pavel Kalinnikov <pavel@cockroachlabs.com>
This commit removes the verbose comparisons in tests, in favor of using
assert/require helpers from the testify packages.
Signed-off-by: Pavel Kalinnikov <pavel@cockroachlabs.com>
Make the field name and comment clearer on the fact that it's used both in
StateProbe and StateReplicate. The old name ProbeSent was slightly confusing,
and also triggered thinking that it's used only in StateProbe.
Signed-off-by: Pavel Kalinnikov <pavel@cockroachlabs.com>
When Inflights to a particular node is full, i.e. MaxInflightMsgs for the
append messages flow is saturated, it is still necessary to continue sending
MsgApp to ensure progress. Currently this is achieved by "forgetting" the first
in-flight message in the window, which frees up quota for one new MsgApp.
This new message is constructed in such a way that it potentially has multiple
entries, or a large entry. The effect of this is that the in-flight limitations
can be exceeded arbitrarily, for as long as the flow to this node continues
being saturated. In particular, if a follower is stuck, the leader will keep
sending entries to it.
This commit makes the MsgApp empty when Inflights is saturated, and prevents
the described leakage of Entries to slow followers.
Signed-off-by: Pavel Kalinnikov <pavel@cockroachlabs.com>
Make it less verbose by omitting the values for the steady state.
Also rearrange the order so that information that is typically more
relevant is printed first.
Mechanically extract `progressTracker`, `Progress`, and `inflights`
to their own package named `tracker`. Add lots of comments in the
progress, and take the opportunity to rename and clarify various
fields.
