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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:
" `7 C' ~/ E; W! D R4 yroot@tl:~# ipcs -l
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: A0 j5 E) u9 X, j) S- k# i* H% X------ Shared Memory Limits --------3 n6 `& p8 [ q4 s
max number of segments = 4096( l3 X; n* c4 P9 v% z
max seg size (kbytes) = 32768
* {" A( B' V9 e4 S5 `$ e3 ]* P' c0 dmax total shared memory (kbytes) = 8388608
* }6 i& h% n4 i% ^1 X+ Fmin seg size (bytes) = 1
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------ Semaphore Limits --------
- I! o/ e( w O2 mmax number of arrays = 128$ Z( q' y9 N% @( c7 {) V0 @
max semaphores per array = 250
$ |. N% ?( A$ r$ F* M2 r Bmax semaphores system wide = 32000. W1 r7 Q& w* Y. M
max ops per semop call = 32
& |6 G0 `2 y6 a! d8 [1 i/ h' C+ rsemaphore max value = 32767
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------ Messages Limits --------
2 @2 {# Y& R3 X; N# N0 `6 i+ Dmax queues system wide = 178: M' I- i* K, H1 P* s' v
max size of message (bytes) = 8192 U% P8 C4 V" [7 C: k
default max size of queue (bytes) = 16384
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但是,用ipcs -a ! H. W# z) M" @* s
root@tl:~# ipcs -a
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9 c6 ?2 c9 w5 i+ |1 p5 c4 x------ Shared Memory Segments --------% }+ Q9 ?( q b. F: N, D# Y4 W# g y: _
key shmid owner perms bytes nattch status 0 G! _( A( [% ^) m' P3 }- r* R0 j# D
0x00000000 0 root 600 1024 1 dest
4 E0 p; g5 p& ?0 ^0x00000000 196609 root 600 1024 1 dest
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------ Semaphore Arrays --------
5 k+ ~7 k+ g% t( [( vkey semid owner perms nsems
0 G7 M# n5 |% R& \2 @! v9 @5 F0x6411074d 0 root 600 1
5 M+ I9 e, c7 m1 k/ T0 z2 t _0x64110957 163841 root 600 1 5 ?5 @, [4 X9 D4 D* m0 k
0x641109a1 196610 root 600 1
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------ Message Queues --------6 X" a6 L. o& A3 F+ D1 T$ M
key msqid owner perms used-bytes messages 3 y1 s$ k* L9 k7 w/ x# T! X) I
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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?8 p7 T( J ]4 J
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