Re: `pv` rates
On Mon 02 Aug 2021 at 15:09:38 (-0400), Stefan Monnier wrote:
> >> If it weren't for the first sometimes changing to
> >> 44.xKiB/s it'd be hard to know which is which (IIUC the average is
> >> higher because occasionally the drive gives a more reasonable transfer
> >> rate than that measly 45kB/s).
> >
> > So now we're left wondering how you came by this situation. Perhaps
> > you slumped onto the Return key, then woke up after a few minutes,
> > having missed the initial burst that gave rise to the average being
> > more than 50% faster than the current rate.
>
> I don't know either. Reading the whole drive would take a few years, so
> I'm only fetching the few parts which have changed since the last
> backup, and when I look the rate seems to be always ~45kB/s, but
> obviously there have to be bursts at higher speeds (presumably because
> the drive's defect doesn't affect every cylinder in the same way or
> something like that. E.g. the average has moved up to ~80kB/s since my
> last message).
Yes, perhaps because the drive is broken, there was no initial burst
(which usually makes it obvious). 45kB/s is so slow that any normal-speed
bursts might be too short to notice unless you're watching like a hawk.
Most transfers are more likely to look something like below (narrowed).
Nice command though (I too had never noticed it), especially the wall
time, though I would say that having both I&e is less sensible than a&r
when using the command for real. Perhaps I should have used -i myself …
Cheers,
David.
$ pv -parIe <2021-01-20-inauguration-biden-harris-C-qYgs_yOXA.webm >/tmp/copy
[86.8MiB/s] [86.8MiB/s] [> ] 1% ETA 0:01:25 ETA 18:51:46
[93.2MiB/s] [89.9MiB/s] [> ] 2% ETA 0:01:22 ETA 18:51:44
[91.9MiB/s] [90.6MiB/s] [> ] 3% ETA 0:01:20 ETA 18:51:43
[93.1MiB/s] [91.2MiB/s] [=> ] 4% ETA 0:01:18 ETA 18:51:42
[92.1MiB/s] [91.4MiB/s] [==> ] 6% ETA 0:01:17 ETA 18:51:42
[85.2MiB/s] [90.4MiB/s] [==> ] 7% ETA 0:01:17 ETA 18:51:43
[41.6MiB/s] [82.5MiB/s] [==> ] 7% ETA 0:01:22 ETA 18:51:49
[51.6MiB/s] [79.2MiB/s] [===> ] 8% ETA 0:01:27 ETA 18:51:55
[3.90MiB/s] [66.4MiB/s] [===> ] 8% ETA 0:01:37 ETA 18:52:06
[10.7MiB/s] [64.5MiB/s] [===> ] 8% ETA 0:01:47 ETA 18:52:17
[3.83MiB/s] [58.6MiB/s] [===> ] 8% ETA 0:01:57 ETA 18:52:28
[3.56MiB/s] [53.5MiB/s] [===> ] 8% ETA 0:02:06 ETA 18:52:38
[3.80MiB/s] [50.4MiB/s] [===> ] 8% ETA 0:02:16 ETA 18:52:49
[5.78MiB/s] [47.3MiB/s] [===> ] 8% ETA 0:02:26 ETA 18:53:00
[5.86MiB/s] [44.4MiB/s] [===> ] 8% ETA 0:02:34 ETA 18:53:09
[2.54MiB/s] [41.6MiB/s] [===> ] 8% ETA 0:02:44 ETA 18:53:20
[2.79MiB/s] [39.4MiB/s] [===> ] 8% ETA 0:02:53 ETA 18:53:30
[72.2MiB/s] [41.0MiB/s] [===> ] 9% ETA 0:02:46 ETA 18:53:24
[93.1MiB/s] [43.7MiB/s] [====> ] 10% ETA 0:02:34 ETA 18:53:13
[92.4MiB/s] [46.2MiB/s] [=====> ] 12% ETA 0:02:24 ETA 18:53:04
[67.3MiB/s] [47.2MiB/s] [======> ] 13% ETA 0:02:19 ETA 18:53:00
[92.9MiB/s] [49.2MiB/s] [======> ] 14% ETA 0:02:11 ETA 18:52:53
[87.6MiB/s] [50.9MiB/s] [=======> ] 15% ETA 0:02:05 ETA 18:52:48
[45.0MiB/s] [50.6MiB/s] [=======> ] 16% ETA 0:02:04 ETA 18:52:48
[48.6MiB/s] [50.6MiB/s] [=======> ] 16% ETA 0:02:04 ETA 18:52:49
[45.1MiB/s] [50.4MiB/s] [========> ] 17% ETA 0:02:04 ETA 18:52:50
[20.4MiB/s] [49.2MiB/s] [========> ] 17% ETA 0:02:06 ETA 18:52:53
[28.5MiB/s] [48.5MiB/s] [========> ] 17% ETA 0:02:08 ETA 18:52:56
[35.2MiB/s] [48.0MiB/s] [========> ] 18% ETA 0:02:08 ETA 18:52:57
[4.75MiB/s] [46.5MiB/s] [========> ] 18% ETA 0:02:12 ETA 18:53:02
[1.30MiB/s] [45.1MiB/s] [========> ] 18% ETA 0:02:16 ETA 18:53:07
[3.25MiB/s] [43.8MiB/s] [========> ] 18% ETA 0:02:20 ETA 18:53:12
[2.93MiB/s] [42.5MiB/s] [========> ] 18% ETA 0:02:24 ETA 18:53:17
[2.67MiB/s] [41.3MiB/s] [========> ] 18% ETA 0:02:28 ETA 18:53:22
[4.17MiB/s] [40.2MiB/s] [========> ] 18% ETA 0:02:32 ETA 18:53:27
[2.52MiB/s] [39.3MiB/s] [========> ] 18% ETA 0:02:36 ETA 18:53:32
[5.58MiB/s] [38.4MiB/s] [========> ] 18% ETA 0:02:40 ETA 18:53:37
[3.75MiB/s] [37.5MiB/s] [========> ] 18% ETA 0:02:43 ETA 18:53:41
[3.90MiB/s] [36.6MiB/s] [========> ] 18% ETA 0:02:47 ETA 18:53:46
[55.0MiB/s] [37.0MiB/s] [=========> ] 19% ETA 0:02:44 ETA 18:53:44
[47.9MiB/s] [37.3MiB/s] [==========> ] 20% ETA 0:02:41 ETA 18:53:42
[83.6MiB/s] [38.4MiB/s] [==========> ] 21% ETA 0:02:35 ETA 18:53:37
[72.3MiB/s] [39.2MiB/s] [===========> ] 22% ETA 0:02:30 ETA 18:53:33
[ 105MiB/s] [40.7MiB/s] [===========> ] 23% ETA 0:02:22 ETA 18:53:26
[93.8MiB/s] [41.9MiB/s] [============> ] 24% ETA 0:02:15 ETA 18:53:20
^C
$
Cheers,
David.
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