Sybase 12.4.2 Server User Manual


 
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.