Adding and clearing a new drive - how slow?

[johnieutah]

So I just added a new drive to my Unraid 6 setup.  When I say new, I mean to this server.  Previously the drive had been used in an Unraid 5 build, formatted in ReiserFS (of course).

 

So first question is, I was surprised to be told that I need to clear the drive.  I'm pretty sure for a couple of the other drives, I didn't need to clear them first.

 

Second question, how slow is the clearing process? (through the web UI, i.e. this is not the pre_clear script running separately from the command line).  This 750GB Samsung drive is only 60% through after 13.5 hours...  Is this normal?

toaster-syslog-20150619-0818.zip

[garycase]

Yes, it's normal that it takes a long time.    In fact, this was the original motivation (years ago) for JoeL to write the pre-clear script ==> it allows drives to be cleared BEFORE they are added to the server, so they can be added VERY quickly.

 

When you clear them in the array, the entire array is unavailable until the clearing process completes.  Given that you're already close to 2/3rds done, I'd just wait it out at this point; but in the future you may want to use the pre-clear script.

 

Anytime you want to add a drive to the protected array, it must be cleared.  You likely added your other drives before you had done a parity sync (perhaps when you were initializing the configuration).  In that case, it's not necessary to clear the drives, since you aren't trying to maintain good parity (yet).

 

[itimpi]

Second question, how slow is the clearing process? (through the web UI, i.e. this is not the pre_clear script running separately from the command line).  This 750GB Samsung drive is only 60% through after 13.5 hours...  Is this normal?

That sounds as if the system may be struggling with that drive.  I would have expected that size drive to finish in an hour or two.  You might want to consider using the Diagnostics option from the Tools tab to get some information that can be posted for others to look at to see if they spot anything.

 

Having said that it is almost certainly not worth aborting the current clear at this point unless you need the array online urgently.

[johnieutah]

Thanks.  Gary once again your presumption is correct 

Yes, in the future, I will be using the pre-clear script for sure.  I had used it before and for whatever reason forgot that the array would be unavailable.

 

Anyhow, I was expecting something around 4-5 hours for a 750GB drive, this looks to be clocking in at 20 or so!

 

One further question: if I want to change disk numbers around afterward, can I do a new config and then use Trust parity?  Will that work ok after such a clearing finishes?

[itimpi]

One further question: if I want to change disk numbers around afterward, can I do a new config and then use Trust parity?  Will that work ok after such a clearing finishes?

Yes as long as you are using the same set of drives.

 

The order of data drives is not critical as far as parity is concerned so shuffling the order is not an issue.