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Poor Disk Performance

Brendan Gregg

From these outputs I try to determine if the problem is: - **The workload**: High-latency disk I/O is commonly caused by the workload applied. Rotational disks have extra latency from head seeks for random I/O, and spin ups from the idle state. Note the sdb latencies range from 32 ms to over 2 seconds! Hit Ctrl-C to end.

article thumbnail

Poor Disk Performance

Brendan Gregg

From these outputs I try to determine if the problem is: - **The workload**: High-latency disk I/O is commonly caused by the workload applied. Rotational disks have extra latency from head seeks for random I/O, and spin ups from the idle state. Note the sdb latencies range from 32 ms to over 2 seconds! Hit Ctrl-C to end.

article thumbnail

Poor Disk Performance

Brendan Gregg

From these outputs I try to determine if the problem is: - **The workload**: High-latency disk I/O is commonly caused by the workload applied. Rotational disks have extra latency from head seeks for random I/O, and spin ups from the idle state. The latencies here look like they are a mix of normal speed (~1.9 Hit Ctrl-C to end.