RE: EMC striping question
Clear. Sure, the cache is nice. EMC are the gods of cacheEventually, the writes have to be made permanent. What happens when the cache is full? Right, EMC blocks io until most of the io has gone to disk. This leaves the poor user waiting, and waiting, and grow a beard. Symmetrix is limited to a 64G cache anyway.I think we should move to OS striping. Thanks. Reply-To: [EMAIL PROTECTED] To: Multiple recipients of list ORACLE-L <[EMAIL PROTECTED]> Date: Fri, 03 Oct 2003 09:09:42 -0800 Why worry about how it gets written. The cache will make any implementation sing like a bird. And if you think you are having problems just add more cache and that will take care of it. - As told to us by a past EMC Sales Weenie -Original Message- Sent: Friday, October 03, 2003 6:50 AM To: Multiple recipients of list ORACLE-L Hi All, Today I saw an archived thread on orafaq about striped volumes in an EMC Symmetrix. Gaja mentioned that writing to a striped volume is performed in a sequential fashion i.e. spindle B will not start writing block 2 before spindle A has completed writing block 1. Is this still true for a Symmetrix with 5568 firmware? Perhaps it's a better idea to let the OS handle the striping? Regards, Hans de Git _ Chatten met je online vrienden via MSN Messenger. http://messenger.msn.nl/ -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Hans de Git INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 http://www.fatcity.com San Diego, California-- Mailing list and web hosting services - To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Tony Johnson INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 http://www.fatcity.com San Diego, California-- Mailing list and web hosting services - To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). _ Chatten met je online vrienden via MSN Messenger. http://messenger.msn.nl/ -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Hans de Git INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 http://www.fatcity.com San Diego, California-- Mailing list and web hosting services - To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
RE: EMC striping question
Why worry about how it gets written. The cache will make any implementation sing like a bird. And if you think you are having problems just add more cache and that will take care of it. - As told to us by a past EMC Sales Weenie -Original Message- Sent: Friday, October 03, 2003 6:50 AM To: Multiple recipients of list ORACLE-L Hi All, Today I saw an archived thread on orafaq about striped volumes in an EMC Symmetrix. Gaja mentioned that writing to a striped volume is performed in a sequential fashion i.e. spindle B will not start writing block 2 before spindle A has completed writing block 1. Is this still true for a Symmetrix with 5568 firmware? Perhaps it's a better idea to let the OS handle the striping? Regards, Hans de Git _ Chatten met je online vrienden via MSN Messenger. http://messenger.msn.nl/ -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Hans de Git INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 http://www.fatcity.com San Diego, California-- Mailing list and web hosting services - To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Tony Johnson INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 http://www.fatcity.com San Diego, California-- Mailing list and web hosting services - To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
RE: EMC striping question
This could be true on the request level. But it will not stop it from pipelining other requests on the spindle level, so that when spindle A is done for request 1 it works on request 2. This increases the overall throughput of the system. Then using Async IO should help here. I'm talking about EMC raid 0+1 hardware striping, if you are talking about RAID-S, this will be a different story because the parity bits needs to be maintained. Regards, Waleed -Original Message- Sent: Friday, October 03, 2003 9:50 AM To: Multiple recipients of list ORACLE-L Hi All, Today I saw an archived thread on orafaq about striped volumes in an EMC Symmetrix. Gaja mentioned that writing to a striped volume is performed in a sequential fashion i.e. spindle B will not start writing block 2 before spindle A has completed writing block 1. Is this still true for a Symmetrix with 5568 firmware? Perhaps it's a better idea to let the OS handle the striping? Regards, Hans de Git _ Chatten met je online vrienden via MSN Messenger. http://messenger.msn.nl/ -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Hans de Git INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 http://www.fatcity.com San Diego, California-- Mailing list and web hosting services - To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Khedr, Waleed INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 http://www.fatcity.com San Diego, California-- Mailing list and web hosting services - To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
Re: EMC striping question
Sorry Matt, Just checked with EMC netherlands, unfortunately, I'm right. About the cache: a shared cache is easily flooded with large io's. Reply-To: [EMAIL PROTECTED] To: Multiple recipients of list ORACLE-L <[EMAIL PROTECTED]> Date: Fri, 03 Oct 2003 06:01:00 -0800 Hi Hans, Absolutely not true, and has not been true for a long time. Writes to an EMC never go directly to disk anyway, and when they do go to disk is purely determined by the microcode algorithms, and will often have nothing to do with stripe layout at all. Thanks, Matt - Original Message - To: "Multiple recipients of list ORACLE-L" <[EMAIL PROTECTED]> Sent: Friday, October 03, 2003 9:50 AM > Hi All, > > Today I saw an archived thread on orafaq about striped volumes in an EMC > Symmetrix. Gaja mentioned that writing to a striped volume is performed in a > sequential fashion i.e. spindle B will not start writing block 2 before > spindle A has completed writing block 1. > > Is this still true for a Symmetrix with 5568 firmware? > Perhaps it's a better idea to let the OS handle the striping? > > Regards, > Hans de Git > > _ > Chatten met je online vrienden via MSN Messenger. http://messenger.msn.nl/ > > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: Hans de Git > INET: [EMAIL PROTECTED] > > Fat City Network Services-- 858-538-5051 http://www.fatcity.com > San Diego, California-- Mailing list and web hosting services > - > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > the message BODY, include a line containing: UNSUB ORACLE-L > (or the name of mailing list you want to be removed from). You may > also send the HELP command for other information (like subscribing). > -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Matthew Zito INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 http://www.fatcity.com San Diego, California-- Mailing list and web hosting services - To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). _ Hotmail en Messenger on the move http://www.msn.nl/communicatie/smsdiensten/hotmailsmsv2/ -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Hans de Git INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 http://www.fatcity.com San Diego, California-- Mailing list and web hosting services - To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
Re: EMC striping question
Hi Hans, Absolutely not true, and has not been true for a long time. Writes to an EMC never go directly to disk anyway, and when they do go to disk is purely determined by the microcode algorithms, and will often have nothing to do with stripe layout at all. Thanks, Matt - Original Message - To: "Multiple recipients of list ORACLE-L" <[EMAIL PROTECTED]> Sent: Friday, October 03, 2003 9:50 AM > Hi All, > > Today I saw an archived thread on orafaq about striped volumes in an EMC > Symmetrix. Gaja mentioned that writing to a striped volume is performed in a > sequential fashion i.e. spindle B will not start writing block 2 before > spindle A has completed writing block 1. > > Is this still true for a Symmetrix with 5568 firmware? > Perhaps it's a better idea to let the OS handle the striping? > > Regards, > Hans de Git > > _ > Chatten met je online vrienden via MSN Messenger. http://messenger.msn.nl/ > > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: Hans de Git > INET: [EMAIL PROTECTED] > > Fat City Network Services-- 858-538-5051 http://www.fatcity.com > San Diego, California-- Mailing list and web hosting services > - > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > the message BODY, include a line containing: UNSUB ORACLE-L > (or the name of mailing list you want to be removed from). You may > also send the HELP command for other information (like subscribing). > -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Matthew Zito INET: [EMAIL PROTECTED] Fat City Network Services-- 858-538-5051 http://www.fatcity.com San Diego, California-- Mailing list and web hosting services - To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
