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您好, 在使用OMAPL138 evm过程中,我使用了MessageQ和ringIO来传输数据。利用ipcs -l ,情况如下:
$ X) J R# i0 H) S3 o7 S) ?root@tl:~# ipcs -l
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( E2 t/ G' E7 _9 c* {; E5 G' e0 u5 G------ Shared Memory Limits --------
: u+ Z E9 i: a% `: {3 v# lmax number of segments = 4096# \+ `4 {0 p5 D- }- u
max seg size (kbytes) = 32768
4 W& U3 W) [2 T+ G( z1 H+ k) | @max total shared memory (kbytes) = 83886085 I: Q7 S$ c2 o( K% y4 l& u
min seg size (bytes) = 1
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: e& w) Q* ~) W+ x------ Semaphore Limits --------7 B+ o) D+ B% p2 L: E$ j
max number of arrays = 128
7 A; O+ g8 B" J7 wmax semaphores per array = 250. n: s4 l2 r# B4 Y
max semaphores system wide = 32000
* y$ x: i M* o4 hmax ops per semop call = 32
/ b- ^6 H4 B& k: w. {semaphore max value = 32767
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------ Messages Limits --------
6 S1 D& z; }6 E) i' U: K4 _max queues system wide = 178
, g0 c4 @0 F. A% k emax size of message (bytes) = 8192. f+ u) ] E I) A0 J9 b5 D6 J
default max size of queue (bytes) = 16384. b0 t9 _; l m$ j, G, e/ O; G
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但是,用ipcs -a & T+ d+ j5 Z" m7 i9 \. c3 E# U
root@tl:~# ipcs -a
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0 k- s+ B' a7 D4 a2 Y0 i------ Shared Memory Segments --------
4 a O* `1 _9 p: o/ I. Ckey shmid owner perms bytes nattch status $ S4 [' \+ s4 R8 F
0x00000000 0 root 600 1024 1 dest 4 `% c' D. u. z9 n1 J
0x00000000 196609 root 600 1024 1 dest
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8 D* A, ?& B5 \) H' P/ R3 `% V------ Semaphore Arrays --------* q! U: E) D- L+ p
key semid owner perms nsems
: G) R) `- x3 Z5 e$ ?9 x0x6411074d 0 root 600 1 " |8 q% }% [9 `: R
0x64110957 163841 root 600 1 - u) D1 i6 D% m, I
0x641109a1 196610 root 600 1
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* n) P9 K8 X) B- Q" [8 r3 |2 ^' q------ Message Queues --------
) d& X5 U/ i0 q: z5 m: ^key msqid owner perms used-bytes messages , h' s: p4 m v0 k3 z2 N
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请问,我的共享内存使用大小为 (float *)ring_buffer_acquired(ad->buffer, 2320 * sizeof(float)*18); 远大于1024BYTE ,请问为什么?
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