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Small correction in http://www.postgresql.org/docs/9.0/interactive/wal-reliability.html
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* Small correction in http://www.postgresql.org/docs/9.0/interactive/wal-reliability.html
@ 2011-06-17 11:55 Achilleas Mantzios <[email protected]>
  2011-06-18 02:54 ` Re: Small correction in http://www.postgresql.org/docs/9.0/interactive/wal-reliability.html Greg Smith <[email protected]>
  0 siblings, 1 reply; 3+ messages in thread

From: Achilleas Mantzios @ 2011-06-17 11:55 UTC (permalink / raw)
  To: pgsql-docs

It reads :
'On FreeBSD, IDE drives can be queried using atacontrol, and SCSI drives using sdparm. '
but it should be:
'On FreeBSD, IDE drives can be queried using atacontrol, and SCSI drives using camcontrol. '
-- 
Achilleas Mantzios



^ permalink  raw  reply  [nested|flat] 3+ messages in thread

* Re: Small correction in http://www.postgresql.org/docs/9.0/interactive/wal-reliability.html
  2011-06-17 11:55 Small correction in http://www.postgresql.org/docs/9.0/interactive/wal-reliability.html Achilleas Mantzios <[email protected]>
@ 2011-06-18 02:54 ` Greg Smith <[email protected]>
  2011-10-10 17:27   ` Re: Small correction in http://www.postgresql.org/docs/9.0/interactive/wal-reliability.html Robert Haas <[email protected]>
  0 siblings, 1 reply; 3+ messages in thread

From: Greg Smith @ 2011-06-18 02:54 UTC (permalink / raw)
  To: pgsql-docs

On 06/17/2011 07:55 AM, Achilleas Mantzios wrote:
> It reads :
> 'On FreeBSD, IDE drives can be queried using atacontrol, and SCSI drives using sdparm.'
> but it should be:
> 'On FreeBSD, IDE drives can be queried using atacontrol, and SCSI drives using camcontrol.'
>    

FreeBSD's Common Access Method (CAM) looks to be the preferred driver 
layer to interrogate.  sdparm is available on Linux and FreeBSD, but 
it's a second-class citizen talking to CAM on the latter.  To quote from 
one of the docs on it, FreeBSD sdparm "SCSI commands are routed through 
the CAM pass-through interface".  Talking directly to it with camcontrol 
does seem to be the preferred route for some things.

However, the UI to sdparm is a bit easier to use when it is available.  
Actually changing the write cache state with camcontrol requires black 
magic--you have to construct the right SCSI packet by hand.  I can't 
find any example.

Bruce just touched this section of the docs recently, so this part 
actually reads just:

          SCSI drives use <command>sdparm</command>.

Now.  Perhaps the following makes sense:

          SCSI drives can be queried using <command> camcontrol 
identify</command>, and the write cache both queried and changed using 
<command>sdparm</command> when available.

-- 
Greg Smith   2ndQuadrant US    [email protected]   Baltimore, MD
PostgreSQL Training, Services, and 24x7 Support  www.2ndQuadrant.us





^ permalink  raw  reply  [nested|flat] 3+ messages in thread

* Re: Small correction in http://www.postgresql.org/docs/9.0/interactive/wal-reliability.html
  2011-06-17 11:55 Small correction in http://www.postgresql.org/docs/9.0/interactive/wal-reliability.html Achilleas Mantzios <[email protected]>
  2011-06-18 02:54 ` Re: Small correction in http://www.postgresql.org/docs/9.0/interactive/wal-reliability.html Greg Smith <[email protected]>
@ 2011-10-10 17:27   ` Robert Haas <[email protected]>
  0 siblings, 0 replies; 3+ messages in thread

From: Robert Haas @ 2011-10-10 17:27 UTC (permalink / raw)
  To: Greg Smith <[email protected]>; +Cc: pgsql-docs

On Fri, Jun 17, 2011 at 10:54 PM, Greg Smith <[email protected]> wrote:
> On 06/17/2011 07:55 AM, Achilleas Mantzios wrote:
>>
>> It reads :
>> 'On FreeBSD, IDE drives can be queried using atacontrol, and SCSI drives
>> using sdparm.'
>> but it should be:
>> 'On FreeBSD, IDE drives can be queried using atacontrol, and SCSI drives
>> using camcontrol.'
>>
>
> FreeBSD's Common Access Method (CAM) looks to be the preferred driver layer
> to interrogate.  sdparm is available on Linux and FreeBSD, but it's a
> second-class citizen talking to CAM on the latter.  To quote from one of the
> docs on it, FreeBSD sdparm "SCSI commands are routed through the CAM
> pass-through interface".  Talking directly to it with camcontrol does seem
> to be the preferred route for some things.
>
> However, the UI to sdparm is a bit easier to use when it is available.
>  Actually changing the write cache state with camcontrol requires black
> magic--you have to construct the right SCSI packet by hand.  I can't find
> any example.
>
> Bruce just touched this section of the docs recently, so this part actually
> reads just:
>
>         SCSI drives use <command>sdparm</command>.
>
> Now.  Perhaps the following makes sense:
>
>         SCSI drives can be queried using <command> camcontrol
> identify</command>, and the write cache both queried and changed using
> <command>sdparm</command> when available.

Done, in master and REL9_1_STABLE.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company




^ permalink  raw  reply  [nested|flat] 3+ messages in thread


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2011-06-17 11:55 Small correction in http://www.postgresql.org/docs/9.0/interactive/wal-reliability.html Achilleas Mantzios <[email protected]>
2011-06-18 02:54 ` Greg Smith <[email protected]>
2011-10-10 17:27   ` Robert Haas <[email protected]>

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