1
0
mirror of https://github.com/moparisthebest/curl synced 2025-01-08 12:28:06 -05:00

updated after discussions and thinking

This commit is contained in:
Daniel Stenberg 2006-07-07 07:22:05 +00:00
parent 05edd48ad0
commit 2a0e41cab9

View File

@ -22,34 +22,48 @@ subsequent) ones need to be attached to the first handle so that it can send
its request on the same connection and then sit and wait until its response its request on the same connection and then sit and wait until its response
comes. comes.
To ponder about: API
- Explicitly ask for pipelining handle X and handle Y ? It isn't always that We add a new option to curl_multi_setopt() called CURLMOPT_PIPELINING that
easy for an app to do this association. The lib should probably still resolve enables "attempted pipelining" and then all easy handles used on that handle
the second one properly to make sure that they actually _can_ be considered will attempt to use an existing pipeline.
for pipelining. Also, asking for explicit pipelining on handle X may be
tricky when handle X get a closed connection.
- Have an option like "attempt pipelining" and then it _may_ use that if an Decisions Already Made
existing connection is already present against our target HTTP server? May
cause funny effects if the first transfer is a slow big file and the second - A pipeline is only created if a previous connection exists to the same IP
is a very small one... Also probably requires some kind of notification address that the new request is being made to use.
support so that the app can get to know that the handle is put "in line" for
pipelining. - Pipelines are only supported for HTTP(S) as no other currently supported
protocol has features resemembling this, but we still name this feature
plain 'pipelining' to possibly one day support it for other protocols as
well.
- When a pipeline is in use, we must take precautions so that when used easy
handles (i.e those who still wait for a response) are removed from the multi
handle, we must deal with the outstanding response nicely.
- Explicitly asking for pipelining handle X and handle Y won't be supported.
It isn't easy for an app to do this association. The lib should probably
still resolve the second one properly to make sure that they actually _can_
be considered for pipelining. Also, asking for explicit pipelining on handle
X may be tricky when handle X get a closed connection.
To Ponder About
- We need options to control max pipeline length, and probably how to behave - We need options to control max pipeline length, and probably how to behave
if we reach that limit. if we reach that limit. As was discussed on the list, it can probably be
made very complicated, so perhaps we can think of a way to pass all
- When a pipeline is in use, we must take precautions so that we either don't variables involved to a callback and let the application decide how to act
allow the used handles (i.e those who still wait for a response) to be in specific situations. Either way, these fancy options are only interesting
removed, or we allow removal but still deal with the outstanding response to work on when everything is working and we have working apps to test with.
somehow.
- Currently (before pipelining) we do not have any code or concept that lets - Currently (before pipelining) we do not have any code or concept that lets
multiple handles share the same physical connection. We need a lock concept multiple handles share the same physical connection. We need to carefully
and carefully make sure that each handle knows exactly what they can do and make sure that each easy handle knows exactly what they can do and when, on
when, on the shared connection. the shared connection.
- We need to keep a linked list of each handle that is part of a single pipe - We need to keep a linked list of each handle that is part of a single pipe
so that if it breaks, we know which handles that need to resend their so that if it breaks, we know which handles that need to resend their
requests. requests. The pipe linked-lists could very well be "held" in the multi
handle struct so that they won't "belong" to a particular easy handle that
happens to be part of the pipeline during a certain period.