| 1 |
>> You should definitely determine the right value for ashift on pool |
| 2 |
>> creation |
| 3 |
>> (it controls the alignment on the medium). It's an option that you afaik |
| 4 |
>> can only set |
| 5 |
>> on filesystem creation and therefore needs a restart from scratch if you |
| 6 |
>> get it |
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>> wrong. |
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>> According to the illumos wiki it's possible to run a mixed pool (if you |
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>> have |
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>> drives requiring different alignments[1]) |
| 11 |
>> If in doubt: ask ryao (iirc given the right information he can tell you |
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>> which |
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>> are the right options for you if you can't deduce it yourself). |
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>> Choosing the wrong alignment can cause severe performance loss (that's not |
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>> a ZFS issue but happened when 4k sector drives appeared and tools like |
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>> fdisk |
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>> weren't aware of this). |
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> |
| 19 |
> Yikes... |
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> |
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> Ok, shouldn't there be a tool or tools to help with this? Ie, boot up on a |
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> bootable tools disk on the system with all drives connected, then let it |
| 23 |
> 'analyze' your system, maybe ask you some questions (ie, how you will be |
| 24 |
> configuring the drives/RAID, etc), then spit out an optimized config for |
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> you? |
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|
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I'm also interested to know the procedure for getting this right. |
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|
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> It is starting to sound like you need to be a dang engineer just to use |
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> ZFS... |
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|
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I thought the SSD issue was completely separate from ZFS and |
| 33 |
applicable to any other filesystem as well. Someone please correct me |
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if I'm wrong. |
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- Grant |
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