Sybase 12.4.2 User Manual

Page of 536
CHAPTER 12    Managing System Resources
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Table 12-4: Total available memory by platform
On 64-bit platforms (Tru64, SGI IRIX, and Solaris 64-bit), the only limit is the 
physical size of memory on the system.
For Windows NT systems, see the Adaptive Server IQ Installation and 
Configuration Guide
 for more performance tuning hints, including 
recommendations for small memory configurations.
For UNIX systems only, Adaptive Server IQ provides two command-line 
options that can provide more memory.
Wired memory pool
On Digital UNIX, HP and Sun platforms, you can designate a specified amount 
of memory as “wired” memory. This memory is locked down so that it cannot 
be paged. Wired memory can improve performance. To create a pool of 
“wired” memory on these UNIX platforms only, specify the 
-iqwmem
 
command-line switch, indicating the number of MB of wired memory. The 
maximum value for 
-iqwmem
 varies by platform:
3800 on Sun
2000 on HP UNIX
no real maximum for DEC
For example, to add 1GB of wired memory, you specify:
-iqwmem 1000
 Warning! 
Use this switch only if you have enough memory to dedicate some 
of it for this purpose. Otherwise, you can cause serious performance 
degradation.
Platform
Total memory available
CompaqTru64 (Digital UNIX)
Effectively unlimited
HP UNIX
3GB
a
IBM RS6000 AIX
2GB
a
SGI IRIX
Effectively unlimited
Sun Solaris 32-bit
3.3GB
Sun Solaris 64-bit
Effectively unlimited
Windows NT
b
2.5GB
a
You must specify the 
-iqsmem
 option to get this much memory on HP UNIX and 
AIX.
b
You need Windows NT Enterprise to get this much memory.