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Diffstat (limited to 'man')
| -rw-r--r-- | man/man8/zinject.8 | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/man/man8/zinject.8 b/man/man8/zinject.8 index c21d66ac4..90df4fb91 100644 --- a/man/man8/zinject.8 +++ b/man/man8/zinject.8 @@ -43,6 +43,39 @@ Cancel injection records. .B "zinject \-d \fIvdev\fB \-A <degrade|fault> \fIpool\fB Force a vdev into the DEGRADED or FAULTED state. .TP +.B "zinject -d \fIvdev\fB -D latency:lanes \fIpool\fB + +Add an artificial delay to IO requests on a particular +device, such that the requests take a minimum of 'latency' +milliseconds to complete. Each delay has an associated +number of 'lanes' which defines the number of concurrent +IO requests that can be processed. + +For example, with a single lane delay of 10 ms (-D 10:1), +the device will only be able to service a single IO request +at a time with each request taking 10 ms to complete. So, +if only a single request is submitted every 10 ms, the +average latency will be 10 ms; but if more than one request +is submitted every 10 ms, the average latency will be more +than 10 ms. + +Similarly, if a delay of 10 ms is specified to have two +lanes (-D 10:2), then the device will be able to service +two requests at a time, each with a minimum latency of +10 ms. So, if two requests are submitted every 10 ms, then +the average latency will be 10 ms; but if more than two +requests are submitted every 10 ms, the average latency +will be more than 10 ms. + +Also note, these delays are additive. So two invocations +of '-D 10:1', is roughly equivalent to a single invocation +of '-D 10:2'. This also means, one can specify multiple +lanes with differing target latencies. For example, an +invocation of '-D 10:1' followed by '-D 25:2' will +create 3 lanes on the device; one lane with a latency +of 10 ms and two lanes with a 25 ms latency. + +.TP .B "zinject \-d \fIvdev\fB [\-e \fIdevice_error\fB] [\-L \fIlabel_error\fB] [\-T \fIfailure\fB] [\-F] \fIpool\fB" Force a vdev error. .TP |