John Doe wrote:
> From: Drew Weaver <drew.wea...@thenap.com>
>
>> If these drives do not have TLER do not use them with LSI controllers.
>
> Not sure about TLER on those Plextors...
<snip>
TLER would only show up on something that looks at a *very* low level on the
physical drive. What I know is that you can see it with smartctl - from the man
page: scterc[,READTIME,WRITETIME] - [ATA only] prints values and
descriptions of the SCT Error Recovery Control settings.
These
are equivalent to TLER (as used by Western Digital), CCTL (as
used by Samsung and Hitachi) and ERC (as used by Seagate).
READ-
TIME and WRITETIME arguments (deciseconds) set the specified
values. Values of 0 disable the feature, other values less than
65 are probably not supported. For RAID configurations, this is
typically set to 70,70 deciseconds.
Note that knowing this was the result of a *lot* of research a couple-or so
years ago. One *good* thing *seems* to be WD's new Red line, which is targeted
toward NAS, they say... because they've put TLER back to something appropriate,
like 7 sec or so, where it was 2 *minutes* for their "desktop" drives, and they
disallowed changing it in firmware around '09, and the other OEMs followed
suit. What makes Red good, if they work, is that they're only about one-third
more than the low-cost drives, where the "server-grade" drives are 2-3 *times*
the cost (look at the price of Seagate Constellations, for example).
----
I would also like to note that up until Red were released to had to use RE to
get TLER, and now apparently RE, SE, and RED (cost in that order) all support
TLER.
The thing that worries me about RED is that they're listed as only supporting
up to 5 drives in an array, -- how are they limiting that?
I think they probably could've just merged RED and SE into one line of drives
but I guess they limited RED to 3TB so if you want a 4TB part you have to get
the SE.
Something in the back of my mind tells me that RE, SE, and Red are the exact
same hardware with different FW.
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