Perviously, we only use 8bits from member identification
in id generation. The conflict rate is A(256,3)/256^3, which
is around 1%. Now we use 16bites to reduce the rate to 0.005%.
We can attach the full member id into id generation if needed...
When raft broadcasts a Grant to all nodes, all nodes must
agree on the same lease ID. Otherwise, attaching a key to
a lease will fail since the lease ID is node-dependent.
This commit adds a new option for activating profiling based on pprof
in etcd process.
- -enable-pprof: boolean type option which activates profiling
For example, if a client URL is http://localhost:12379, users and
developers access heap profiler with this URL:
http://localhost:12379/debug/pprof/heap
Basic support for lease operations like create and revoke.
We still need to:
1. attach keys to leases in KV implmentation if lease field is set
2. leader periodically removes expired leases
3. leader serves keepAlive requests and follower forwards keepAlive
requests to leader.
We want the KV to support recovering from backend to avoid
additional pointer swap. Or we have to do coordination between
etcdserver and API layer, since API layer might have access to
kv pointer and use a closed kv.
This commit fixes the issue of creating member dir before validating
the configuration. When member dir exists, it indicates the local etcd
process is a valid etcd member. So we should only create member dir
after we finish configuration validation, joining validation or
discovery validation.
The raft loop would block on the applier's done channel after
persisting the raft messages; the latency could cause dropped network
messages. Instead, asynchronously notify the applier with a buffered
channel when the raft writes complete.
raft's applyc writes block on the server loop's database IO since
the next applyc read must wait on the db operation to finish.
Instead, stream applyc to a run queue outside the server loop.
This moves the code to create listener and roundTripper for raft communication
to the same place, and use explicit functions to build them. This prevents
possible development errors in the future.
This pairs with remote timeout listeners.
etcd uses timeout listener, and times out the accepted connections
if there is no activity. So the idle connections may time out easily.
Becaus timeout transport doesn't reuse connections, it prevents using
timeouted connection.
This fixes the problem that etcd fail to get version of peers.
