Hello
I have a problem with USB HDD's clocking tens of thousands of head parks when only one per day is needed. C'mon 2.5'' spinners aren't power hogs and are quiet.
Over sata it's easy to disable this hellish behavior but over USB with PrimoCache caching writes it's impossible ? without physically removing HDD from their casing and voiding warranty.
Can we have a setting in PrimoCache that would make sure that a write occured to certain disk every so many seconds ?
If anyone has a better solution please share.
Thx
USB_HDD Head Parking
Re: USB_HDD Head Parking
Well with write caching active on those HDDs any (Write x Time) App won't work.
Re: USB_HDD Head Parking
If the write caching was more frequent than the app's write schedule, it would. You'd end up with an averaged schedule. Have you already made sure the Windows power profile has USB suspend disabled? Also, the 'Average' write cache mode might be the most beneficial, since it literally draws out writes over a period of time instead of bursting them.
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Re: USB_HDD Head Parking
Are you using write caching and deferred writes?
If so, simply measure how long it takes your external HDD to fall asleep and park its heads. Set the deferred writes timeout to lower than that time for parking and you should be done: You write cache will eat up write data and begin waking up the drive if needed, begin writing out data. If you write often enough that the drive stays alive, fine. If not, it won't hurt as the write cache will run full speed and the write back to HDD will happen "in the background".
If you are NOT using any write caching (such as for security/safety reasons, which I can fully understand), then you are facing a delay on every "wake up call" for the drive, correct. In that case try to figure out how to switch the feature off (ask vendor) or extend the delay time to some more acceptable value. Writing forcefully data every "n" seconds to keep a drive alive sounds really really strange to me and I would strongly recommend to avoid such an approach, as it will lead in unnnecessary fragmentation, wear and tear of your drive.
Is the HDD in your external case an "archive" type HDD?
I've seen some of these fall asleep fairly often, as they are designed to read / write data only once in a while and should stay "offline" as long as possible to extend lifetime. Not exactly the kind of drive you should use for frequent read / write operations after all.
If so, simply measure how long it takes your external HDD to fall asleep and park its heads. Set the deferred writes timeout to lower than that time for parking and you should be done: You write cache will eat up write data and begin waking up the drive if needed, begin writing out data. If you write often enough that the drive stays alive, fine. If not, it won't hurt as the write cache will run full speed and the write back to HDD will happen "in the background".
If you are NOT using any write caching (such as for security/safety reasons, which I can fully understand), then you are facing a delay on every "wake up call" for the drive, correct. In that case try to figure out how to switch the feature off (ask vendor) or extend the delay time to some more acceptable value. Writing forcefully data every "n" seconds to keep a drive alive sounds really really strange to me and I would strongly recommend to avoid such an approach, as it will lead in unnnecessary fragmentation, wear and tear of your drive.
Is the HDD in your external case an "archive" type HDD?
I've seen some of these fall asleep fairly often, as they are designed to read / write data only once in a while and should stay "offline" as long as possible to extend lifetime. Not exactly the kind of drive you should use for frequent read / write operations after all.