Re: [Crash-utility] [PATCH] add a new command: ipcs

----- Original Message ----- I see that in all "ipcs -M" displays where there are a number of shared memory pages swapped out, it shows something like this: SHMID_KERNEL KEY SHMID UID PERMS BYTES NATTCH STATUS ffff810026d75ed0 00000000 360452 3369 600 393216 2 dest PAGES ALLOCATED: 96 RESIDENT: 48 SWAPPED: 36 SWAP PERFORMANCE ATTEMPTS: 0 SUCCESSES: 0 VFS_INODE: ffff81003d927d58 where on every one of them, the "SWAP PERFORMANCE" values are always zero. So then I saw that your code just hardwires them to "0L": fprintf(fp, "PAGES ALLOCATED: %ld RESIDENT: %ld SWAPPED: %ld\n", (shm_info.bytes+PAGESIZE()-1) >> PAGESHIFT(), shm_info.rss, shm_info.swap); fprintf(fp, "SWAP PERFORMANCE ATTEMPTS: %ld SUCCESSES: %ld\n", 0L, 0L); fprintf(fp, "VFS_INODE: %lx\n", shm_info.shm_inode); And looking at recent kernel sources, Linux stopped using those two fields since version 2.6 -- it just returns 0 to the SHM_INFO shmctl system call. Here is relevant part of the shmctl(2) man page: SHM_INFO (Linux specific) Returns a shm_info structure whose fields contain information about system resources consumed by shared memory. This struc- ture is defined in <sys/shm.h> if the _GNU_SOURCE feature test macro is defined: struct shm_info { int used_ids; /* # of currently existing segments */ unsigned long shm_tot; /* Total number of shared memory pages */ unsigned long shm_rss; /* # of resident shared memory pages */ unsigned long shm_swp; /* # of swapped shared memory pages */ unsigned long swap_attempts; /* Unused since Linux 2.4 */ unsigned long swap_successes; /* Unused since Linux 2.4 */ }; So that line of output is completely meaningless, and should be dropped entirely. That being the case, I'm now thinking that the -M option may be unnecessary? The shared memory output could be restricted to just 2 lines: SHMID_KERNEL KEY SHMID UID PERMS BYTES NATTCH STATUS ffff810026d75ed0 00000000 360452 3369 600 393216 2 dest PAGES ALLOCATED/RESIDENT/SWAPPED: 96/48/36 VFS_INODE: ffff81003d927d58 Dave