Learn about managing disk I/O for a SAP Sybase IQ
system.
The most important factors in managing disk I/O for a SAP Sybase IQ system are:
- Having enough disk space for queries and loads
- Using that disk space effectively, so that the fastest I/O is available
to support the processing speed of high-powered, multi-CPU systems
The
sp_iqstatus stored procedure indicates the
percentage of space used in the IQ main and temporary stores. If there is not enough temporary
or main dbspace available for a buffer or dbspace allocation request, then the statement
making the request rolls back. You can create a timer-based event to monitor space usage to
help avoid unexpected rollbacks, which may occur in out of space situations on non-privileged
operations.
Disk striping is an important means of obtaining maximum I/O performance. Disk
striping distributes data randomly across multiple disk drives. You can take advantage of disk
striping capabilities in your operating system or disk management software and hardware, as
well as internal striping. Disk striping is enabled by default.