slow write speeds still :cry:

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Re: slow write speeds still :cry:

Postby lundman » Thu Jul 12, 2018 9:19 pm

I think they consider the slow-512-writes to be a feature, in that you can run multiples of those writes and they will all perform the same, and not interfere with other transfers.

But I don't think that is the issue we talk about, your slowdown is something that happens after it has been running for a while, which might be a unique problem to osx we would need to solve.

We do have some changing coming up though, it is possible that the taskq fixes that rottegift is working on might help a little, hopefully he'll make a PR for that soon.
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Re: slow write speeds still :cry:

Postby e8wwv » Tue Jul 17, 2018 9:57 pm

lundman wrote:I think they consider the slow-512-writes to be a feature, in that you can run multiples of those writes and they will all perform the same, and not interfere with other transfers.

But I don't think that is the issue we talk about, your slowdown is something that happens after it has been running for a while, which might be a unique problem to osx we would need to solve.

We do have some changing coming up though, it is possible that the taskq fixes that rottegift is working on might help a little, hopefully he'll make a PR for that soon.


I have to do a reboot before running a tape backup to get full speed. Even something as simple as opening itunes or viewing a few finder windows causes the slowdown. Instead of 125mb/s I'll get 80-90. With torrents its a 50% reduction, never maintains a constant speed until a reboot. Image
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Re: slow write speeds still :cry:

Postby mkush » Wed Jul 18, 2018 5:41 am

That sounds exactly like what I experienced before I set the ARC to 1GB: fast just after reboot, slow thereafter. Dumb question: is your setting of the ARC actually working? Syntax error or something?
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