Technote (FAQ)
Question
Remove Shared Memory Segments
Answer
Directions for removing shared memory segments are as follows: (must be root)
1. Get your SERVERNUM from the onconfig
2. Convert that to hex and add it to 5256 in hex
3. ipcs -m |grep 5256+SERVERNUM(in hex)
4. The ID is the second column in the output. Write down each of the ID numbers.
5. Take the list of IDs and run ipcrm -m ID for each ID.
so an example is as follows:

1. onstat -c |grep SERVERNUM
SERVERNUM 60 # Unique id corresponding to a Dynamic Server Instance

2. 0x5256 + 0x3c = 0x5292

3. ipcs -m |grep 5292
m 121 0x52924801 --rw-rw---- root informix
m 122 0x52924802 --rw-rw---- root informix
m 123 0x52924803 --rw-rw-rw- root informix

4. ipcrm -m 121
ipcrm -m 122
ipcrm -m 123

5. this command will confirm the segment has been removed
ipcs -m |grep 5292

Источник http://www-01.ibm.com/support/docview.wss?uid=swg21326141&myns=swgimgmt&mynp=OCSSGU8G&mync=E