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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:; ^" Y+ D# _- x
root@tl:~# ipcs -l
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v, e) U$ ~% g7 i------ Shared Memory Limits --------5 s' t/ f5 L+ p" W% z: ]* d- D; V. i
max number of segments = 4096$ ^3 Q& W r& h6 z' P' G
max seg size (kbytes) = 327684 W+ d6 g- s# v# `) B, w
max total shared memory (kbytes) = 8388608
. h, Y2 @. @$ B) y! J/ k amin seg size (bytes) = 1
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------ Semaphore Limits --------0 ~3 l9 A9 C5 X4 q: e2 c" H9 C3 ?" D
max number of arrays = 128
9 r8 K X. f- ]' E2 hmax semaphores per array = 250) g. s3 F: v' m; d4 S% T! s v4 D2 O
max semaphores system wide = 320005 Q" G; z0 O4 b& L* {7 l5 P
max ops per semop call = 32
3 W3 _6 I" u+ \; D) jsemaphore max value = 32767
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------ Messages Limits --------
5 N( w. P+ u% j& z; z* d# R/ dmax queues system wide = 178
- N1 F& `9 H* s6 X% emax size of message (bytes) = 8192) m. c# Z8 U B' B+ h+ {
default max size of queue (bytes) = 16384# s$ z, s; G/ L2 l0 c V* t1 U3 r
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但是,用ipcs -a 8 X6 h1 z q4 l" k. S
root@tl:~# ipcs -a* [+ T2 s5 @8 C3 w2 ?; D0 I0 o
5 D8 W9 V9 ?! B- D- q8 T------ Shared Memory Segments --------
], c+ V6 K9 j4 n+ B; ekey shmid owner perms bytes nattch status 6 p# ?- ^9 y/ R! ]$ {5 a
0x00000000 0 root 600 1024 1 dest " F8 N2 {" }" w4 \- v. a$ B$ z
0x00000000 196609 root 600 1024 1 dest
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/ t! R( @ {& U! T& N; h1 [------ Semaphore Arrays --------
% J( W3 z/ k' H: R+ r/ p; rkey semid owner perms nsems 3 C* s& a p- A+ F2 n
0x6411074d 0 root 600 1
# H: N9 _. M! a9 h8 b+ H, X0x64110957 163841 root 600 1
6 P3 h2 Z+ e. a- h& i( f, T& `0x641109a1 196610 root 600 1 - ^, M9 x/ a, P. G
; V @" ~) v9 x0 z( U) r------ Message Queues --------
3 ?( Z2 @5 ~) |0 Wkey msqid owner perms used-bytes messages ' `4 L, N) U: y$ a
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% K8 o6 N# v( z8 }$ c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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