IBM High IOPS Adapter - Hardware User Guide 2.2.3
|
__________________
__
__
8
Adequate system cooling.
To maximize the longevity and performance of an IBM High IOPS Adapter, we recommend at least 300 Linear
Feet per Minute (LFM) of airflow through the system.
In order to protect against thermal damage, the IBM High IOPS Adapter monitors the temperature of its
onboard controller chip (This is reported by the
command line utility as "Internal temperature").
fio-status
The IBM High IOPS Adapter will start throttling write performance once the controller temperature reaches
78°C. If the controller temperature continues to rise, the IBM High IOPS Adapter will shut down once the
controller temperature reaches 85°C.
NOTE
If you experience write-performance throttling due to high temperatures, consult your server's
documentation for details on increasing airflow within your system .
Sufficient system memory (RAM).
The amount of RAM the VSL requires varies according to the average block size written to the device. Using
the average block size table below, you can estimate the amount of system memory needed. You can reduce
worst-case memory use by formatting your IBM High IOPS Adapter with a 4K sector size and thereby force
the average written block size to be 4K or greater.
Note however, that for many systems, even those formatted with 512 byte sectors, actual memory utilization
typically tracks with I/O operations on 4k or larger chunks of data.
At various block sizes, the following table shows the upper limit of RAM that may be required of your system for
every 80 GB of IBM High IOPS Adapter storage space used.
Average Written Block Size (bytes) RAM Usage (MB) per 80GB of storage space
8192
225
4096 (Most common)
425
2048
825
1024
1600
512
3175
For example, if your system is equipped with a IBM High IOPS Duo Adapter, formatted to use 4,096 byte sectors,
your system may require as much as:
(425 MB of RAM / 80 GB) x (640 GB) =
for use by the IBM High
3,400 MB (or around 3.32 GB) of system RAM
IOPS Duo Adapter driver.
IBM High IOPS Duo Adapter Requirements
In addition to the IBM High IOPS Duo Adapter cooling and RAM requirements given above, the IBM High IOPS
Duo Adapter requires at least:
A PCIe Gen1 x8 slot or a PCIe Gen2 x4 slot.
