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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:
1 z8 x, L! A' B: droot@tl:~# ipcs -l
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' h/ y) f: H+ E, j$ a4 x* _8 D------ Shared Memory Limits --------
$ P4 y. F9 j+ v* smax number of segments = 4096
! N$ A4 x0 n; |% t; nmax seg size (kbytes) = 32768
6 I6 j7 j9 H4 y2 Zmax total shared memory (kbytes) = 8388608* s7 R+ E) o+ O* M+ ?( m$ e) d+ }# T
min seg size (bytes) = 1
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------ Semaphore Limits --------
7 \" p" C3 E7 j& M+ Y/ s+ x0 h& | ^max number of arrays = 128
8 J" V' p$ \( U* z8 Y: @max semaphores per array = 250
_# I2 Z6 N7 e6 Mmax semaphores system wide = 32000
) z9 h+ `- B* F) x0 F5 tmax ops per semop call = 32! ?, O* a0 J I s# |8 J4 q
semaphore max value = 32767
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------ Messages Limits --------( f" g8 |0 Z2 g0 X G
max queues system wide = 1781 g9 w2 M/ z3 G: j
max size of message (bytes) = 8192
# S- g7 v$ b7 M( b6 R! X$ j! k3 e9 ]default max size of queue (bytes) = 16384
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1 H) G0 R2 f% |$ O但是,用ipcs -a ; Q( O+ ~+ U ]% e5 Y6 U
root@tl:~# ipcs -a
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------ Shared Memory Segments --------- X# c7 S. f- Q3 p: m. V: t
key shmid owner perms bytes nattch status + p0 _4 c2 u6 P0 B$ D4 N+ G& d
0x00000000 0 root 600 1024 1 dest & \" l7 M' a/ }
0x00000000 196609 root 600 1024 1 dest
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5 p0 |4 C8 j! H+ [2 a, Y------ Semaphore Arrays --------
& x- J) H @9 Z9 x8 T. B. @key semid owner perms nsems
1 `6 |9 |1 ` m2 s) Z. d0 [% W0x6411074d 0 root 600 1
. s9 \) ?' q3 o4 L; v" p. F E% O0x64110957 163841 root 600 1
5 {; L( G" N: s) G' `* @: v0x641109a1 196610 root 600 1
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------ Message Queues --------
# J$ W) K) g: r$ ^" Zkey msqid owner perms used-bytes messages
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# n- ~6 n; [( U# n& M/ L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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