Mercurial > hg > nginx-quic
annotate src/core/ngx_shmtx.h @ 6750:cb330cd39030 stable-1.10
HTTP/2: implemented preread buffer for request body (closes #959).
Previously, the stream's window was kept zero in order to prevent a client
from sending the request body before it was requested (see 887cca40ba6a for
details). Until such initial window was acknowledged all requests with
data were rejected (see 0aa07850922f for details).
That approach revealed a number of problems:
1. Some clients (notably MS IE/Edge, Safari, iOS applications) show an error
or even crash if a stream is rejected;
2. This requires at least one RTT for every request with body before the
client receives window update and able to send data.
To overcome these problems the new directive "http2_body_preread_size" is
introduced. It sets the initial window and configures a special per stream
preread buffer that is used to save all incoming data before the body is
requested and processed.
If the directive's value is lower than the default initial window (65535),
as previously, all streams with data will be rejected until the new window
is acknowledged. Otherwise, no special processing is used and all requests
with data are welcome right from the connection start.
The default value is chosen to be 64k, which is bigger than the default
initial window. Setting it to zero is fully complaint to the previous
behavior.
author | Valentin Bartenev <vbart@nginx.com> |
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date | Tue, 24 May 2016 17:37:52 +0300 |
parents | 512c741fa841 |
children |
rev | line source |
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611 | 1 |
2 /* | |
3 * Copyright (C) Igor Sysoev | |
4412 | 4 * Copyright (C) Nginx, Inc. |
611 | 5 */ |
6 | |
7 | |
8 #ifndef _NGX_SHMTX_H_INCLUDED_ | |
9 #define _NGX_SHMTX_H_INCLUDED_ | |
10 | |
11 | |
12 #include <ngx_config.h> | |
13 #include <ngx_core.h> | |
14 | |
15 | |
16 typedef struct { | |
4309
3f6040cd731e
Added shmtx interface to forcibly unlock mutexes.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3909
diff
changeset
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17 ngx_atomic_t lock; |
3f6040cd731e
Added shmtx interface to forcibly unlock mutexes.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3909
diff
changeset
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18 #if (NGX_HAVE_POSIX_SEM) |
3f6040cd731e
Added shmtx interface to forcibly unlock mutexes.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3909
diff
changeset
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19 ngx_atomic_t wait; |
3f6040cd731e
Added shmtx interface to forcibly unlock mutexes.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3909
diff
changeset
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20 #endif |
3f6040cd731e
Added shmtx interface to forcibly unlock mutexes.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3909
diff
changeset
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21 } ngx_shmtx_sh_t; |
3f6040cd731e
Added shmtx interface to forcibly unlock mutexes.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3909
diff
changeset
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22 |
3f6040cd731e
Added shmtx interface to forcibly unlock mutexes.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3909
diff
changeset
|
23 |
3f6040cd731e
Added shmtx interface to forcibly unlock mutexes.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3909
diff
changeset
|
24 typedef struct { |
611 | 25 #if (NGX_HAVE_ATOMIC_OPS) |
26 ngx_atomic_t *lock; | |
3909
0daede16d68b
use POSIX semaphores in shmtx instead of sched_yield()
Igor Sysoev <igor@sysoev.ru>
parents:
2563
diff
changeset
|
27 #if (NGX_HAVE_POSIX_SEM) |
4309
3f6040cd731e
Added shmtx interface to forcibly unlock mutexes.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3909
diff
changeset
|
28 ngx_atomic_t *wait; |
3909
0daede16d68b
use POSIX semaphores in shmtx instead of sched_yield()
Igor Sysoev <igor@sysoev.ru>
parents:
2563
diff
changeset
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29 ngx_uint_t semaphore; |
0daede16d68b
use POSIX semaphores in shmtx instead of sched_yield()
Igor Sysoev <igor@sysoev.ru>
parents:
2563
diff
changeset
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30 sem_t sem; |
0daede16d68b
use POSIX semaphores in shmtx instead of sched_yield()
Igor Sysoev <igor@sysoev.ru>
parents:
2563
diff
changeset
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31 #endif |
611 | 32 #else |
33 ngx_fd_t fd; | |
34 u_char *name; | |
35 #endif | |
3909
0daede16d68b
use POSIX semaphores in shmtx instead of sched_yield()
Igor Sysoev <igor@sysoev.ru>
parents:
2563
diff
changeset
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36 ngx_uint_t spin; |
611 | 37 } ngx_shmtx_t; |
38 | |
39 | |
4309
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Added shmtx interface to forcibly unlock mutexes.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3909
diff
changeset
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40 ngx_int_t ngx_shmtx_create(ngx_shmtx_t *mtx, ngx_shmtx_sh_t *addr, |
3f6040cd731e
Added shmtx interface to forcibly unlock mutexes.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3909
diff
changeset
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41 u_char *name); |
4738
512c741fa841
Fixed typo in a function name.
Ruslan Ermilov <ru@nginx.com>
parents:
4412
diff
changeset
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42 void ngx_shmtx_destroy(ngx_shmtx_t *mtx); |
3909
0daede16d68b
use POSIX semaphores in shmtx instead of sched_yield()
Igor Sysoev <igor@sysoev.ru>
parents:
2563
diff
changeset
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43 ngx_uint_t ngx_shmtx_trylock(ngx_shmtx_t *mtx); |
0daede16d68b
use POSIX semaphores in shmtx instead of sched_yield()
Igor Sysoev <igor@sysoev.ru>
parents:
2563
diff
changeset
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44 void ngx_shmtx_lock(ngx_shmtx_t *mtx); |
0daede16d68b
use POSIX semaphores in shmtx instead of sched_yield()
Igor Sysoev <igor@sysoev.ru>
parents:
2563
diff
changeset
|
45 void ngx_shmtx_unlock(ngx_shmtx_t *mtx); |
4309
3f6040cd731e
Added shmtx interface to forcibly unlock mutexes.
Maxim Dounin <mdounin@mdounin.ru>
parents:
3909
diff
changeset
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46 ngx_uint_t ngx_shmtx_force_unlock(ngx_shmtx_t *mtx, ngx_pid_t pid); |
611 | 47 |
48 | |
49 #endif /* _NGX_SHMTX_H_INCLUDED_ */ |