Now anyone can schedule events and get a callback to work as long
as the user data structure that is added for the event begins
with a kore_event data structure.
All event state is now kept in that kore_event structure and renamed
CONN_[READ|WRITE]_POSSIBLE to KORE_EVENT_[READ|WRITE].
The HTTP layer used to make a copy of each incoming header and its
value for a request. Stop doing that and make HTTP headers zero-copy
all across the board.
This change comes with some api function changes, notably the
http_request_header() function which now takes a const char ** rather
than a char ** out pointer.
This commit also constifies several members of http_request, beware.
Additional rework how the worker processes deal with the accept lock.
Before:
if a worker held the accept lock and it accepted a new connection
it would release the lock for others and back off for 500ms before
attempting to grab the lock again.
This approach worked but under high load this starts becoming obvious.
Now:
- workers not holding the accept lock and not having any connections
will wait less long before returning from kore_platform_event_wait().
- workers not holding the accept lock will no longer blindly wait
an arbitrary amount in kore_platform_event_wait() but will look
at how long until the next lock grab is and base their timeout
on that.
- if a worker its next_lock timeout is up and failed to grab the
lock it will try again in half the time again.
- the worker process holding the lock will when releasing the lock
double check if it still has space for newer connections, if it does
it will keep the lock until it is full. This prevents the lock from
bouncing between several non busy worker processes all the time.
Additional fixes:
- Reduce the number of times we check the timeout list, only do it twice
per second rather then every event tick.
- Fix solo worker count for TLS (we actually hold two processes, not one).
- Make sure we don't accidentally miscalculate the idle time causing new
connections under heavy load to instantly drop.
- Swap from gettimeofday() to clock_gettime() now that MacOS caught up.
build the frame in a kore_buf on the stack and use net_send_stream()
to push it out rather then making yet another copy in net_send().
saves several cpu cycles before the frame starts going out as
we're not allocating a kore_buf, its contents and then memcpy()ing
that contents to a new netbuf.
- Change pools to use mmap() for allocating regions.
- Change kore_malloc() to use pools for commonly sized objects.
(split into multiple of 2 buckets, starting at 8 bytes up to 8192).
- Rename kore_mem_free() to kore_free().
The preallocated pools will hold up to 128K of elements per block size.
In case a larger object is to be allocated kore_malloc() will use
malloc() instead.
This basically turns off the HTTP layer for Kore. It does not
compile in anything for HTTP.
This allows Kore to be used as a network application platform as well.
Added an example for this called nohttp.
Other changes that sneaked in while hacking on this:
* Use calloc(), kill pendantic malloc option.
* Killed off SPDY/3.1 support completely, will be superseded by http2
Note that comes with massive changes to a lot of the core API
functions provided by Kore, these might break your application.
Change the callback prototypes to:
void callback(struct kore_msg *msg, const void *data);
This allows the callbacks to receive the full kore_msg data structure
as sent over the wire (including length and id). Useful for future
additions to the kore_msg structure (such as worker origin).
Several other improvements:
* Accesslog now uses the msg framework as well.
* Websocket WEBSOCKET_BROADCAST_GLOBAL now works.
Small websocket improvement in this commit:
* Build the frame to be sent only once when broadcasting
instead of per connection we are broadcasting towards.
With this framework apps can now send messages between worker processes.
A new API function exists:
int kore_msg_register(u_int8_t id, void (*cb)(const void *, u_int32_t);
This API call allows your app to register a new message callback for a given ID.
You can then send messages on this ID to other workers using:
void kore_msg_send(u_int8_t id, void *data, u_int32_t length);
This framework will interally be used for a few things such as allowing
websocket data to broadcasted between all workers, adding unified caching
and hopefully eventually moving the access log to this as well.
Some internals have changed with this commit:
* worker_clients has been called connections.
* the parent now initializes the net, and event subsystems.
* kore_worker_websocket_broadcast() is dead.
Introduces a few new api functions:
- kore_websocket_handshake(struct http_request *):
Performs the handshake on an HTTP request (coming from page handler)
- kore_websocket_send(struct connection *, u_int8_t, void *, size_t):
Sends data to a websocket connection.
- kore_websocket_broadcast(struct connection *, u_int8_t, void *, size_t, int):
Broadcast the given websocket op and data to all connected
websocket clients on the worker. Note that as of right now
the WEBSOCKET_BROADCAST_GLOBAL scope option does not work
yet and messages broadcasted will be restricted to workers
only.
- kore_worker_websocket_broadcast(struct connection *, void *, void *):
Backend function used by kore_websocket_broadcast().
Could prove useful for developers to have access to.
A simple example is given under examples/websocket.
Known issues:
Kore does not support PING or CONT frames just yet.