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RE: when to use minra ?
by Callaway, Michael 01 Sep '06

01 Sep '06

Quote: "My NDMP tape backups from the R200 are pretty slow. I average about 2 MBytes per sec. Note that backups of other volumes on the R200 work really well, so there is no problem on the R200 or the network." Your 2MB/sec sampling, when was that taken? Was it at the beginning, middle, end of the backup? You -should- be getting a really slow through-put rate at the start of a backup, since ndmp basically walks through and takes a look at each file before actually backing them up. When you have a large volume it will take a while to look at each file, it's worse with volumes that have a large number of small files. We had an 8TB 560ish million file vol that would take forever. It seemed to just sit there practically idle, before it would take off and begin backing up. This was too impractical for such a long time for a single backup, so we changed up our future growth area, and now do a snapmirror each qtree to a single volume and then ndmp that out. It still takes time, but it allows us to get a clean backup of separate areas each within their own timeframe. Anyway, my point being, are you seeing slow movement in just the beginning, are you competing backups, and have you captured peak performance? Also, would it be possible to change the way you store your data, or back up in sections? I know it's not fixing the issue, it's just working around it, but it could either help in the meantime while you look at minra, or possibly become a smoother process for you. -- *------------------- Michael Callaway Server Administrator NTTA/IT 214-461-2033 -------------------- -----Original Message----- From: owner-toasters(a)mathworks.com [mailto:owner-toasters@mathworks.com] On Behalf Of Peter D. Gray Sent: Thursday, August 31, 2006 6:53 PM To: toasters(a)mathworks.com Subject: Re: when to use minra ? Thanks for the replies. Some background on this question. I have 2 filers used for email storage (NFS, attached to 2 mirapoint mail stores). They have lots of small files. I am mirroring these 2 filers to an R200 for backup, but I also take tape copies via NDMP every 30 days or so. The volumes contain about 350GB each of actual data, excluding snapshots, and 5 million files. My NDMP tape backups from the R200 are pretty slow. I average about 2 MBytes per sec. Note that backups of other volumes on te R200 work really well, so there is no problem on the R200 or the network. I saw the comment that turning off minra can have a big impact on backup performance so I thought I would try it. But discovered that the setting would have to be changed on the mirror source which is not so good (maybe). It would be nice if that setting could be changed on the mirror target but not the source, but I can see why that not possible. So, I wondered if I could justify setting minra on on the source volumes but would need some way to predict the impact. It sounds like turing on minra is not usually a good idea, so I guess I am stuck with slow NDMP backups. Just out of interest, does anybody understand why minra has an impact on backup speed. I assume the read ahead does not go past end of file but that is the only explanation I can think of as to why it would have an impact? Regards, pdg -- See mail headers for contact information.

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get rid of a false imported aggregate
by Alexander Schalek 01 Sep '06

01 Sep '06

Hi all, Is there any way except reboot the storage appliance to get rid of a failed aggregate in sysconfig-r? During maintenance work I attached a shelve to the wrong filer b (in a 3020er cluster configuration). I corrected my mistake and now I have a failed aggregate on filer b. filer a has the aggregate imported and online, filer b can see the partner aggregate (disks) but still has the failed aggregate in sysconfig -r. thanks for your help. alex

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Yahoo! News Story - Extreme Makeover: "Star Trek" Edition - Yahoo! News
by Peter D. Gray 01 Sep '06

01 Sep '06

Peter D. Gray (pdg(a)uow.edu.au) has sent you a news article. (Email address has not been verified.) ------------------------------------------------------------ Personal message: Extreme Makeover: "Star Trek" Edition - Yahoo! News http://news.yahoo.com/s/eo/20060901/en_tv_eo/19912 ============================================================ Yahoo! News http://news.yahoo.com/

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Yahoo! News Photo - Yahoo! News Photo
by Peter D. Gray 01 Sep '06

01 Sep '06

Peter D. Gray (pdg(a)uow.edu.au) has sent you a news photo. (Email address has not been verified.) ------------------------------------------------------------ Personal message: Yahoo! News Photo http://news.yahoo.com/photo/060831/photos_fashionwire/574cee2ba0024aefcfce1… ============================================================ Yahoo! News http://news.yahoo.com/

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Yahoo! News Story - Rockabilly singer Simmons dies at 69 - Yahoo! News
by Peter D. Gray 01 Sep '06

01 Sep '06

Peter D. Gray (pdg(a)uow.edu.au) has sent you a news article. (Email address has not been verified.) ------------------------------------------------------------ Personal message: Rockabilly singer Simmons dies at 69 - Yahoo! News http://news.yahoo.com/s/ap/20060831/ap_en_mu/obit_simmons_4 ============================================================ Yahoo! News http://news.yahoo.com/

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Yahoo! News Story - Bartender gets $10,000 tip on $26 tab - Yahoo! News
by Peter D. Gray 01 Sep '06

01 Sep '06

Peter D. Gray (pdg(a)uow.edu.au) has sent you a news article. (Email address has not been verified.) ------------------------------------------------------------ Personal message: Bartender gets $10,000 tip on $26 tab - Yahoo! News http://news.yahoo.com/s/ap/20060831/ap_on_fe_st/ten_grand_tip ============================================================ Yahoo! News http://news.yahoo.com/

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Yahoo! News Story - Prayers held for Egyptian writer Mahfouz - Yahoo! News
by Peter D. Gray 31 Aug '06

31 Aug '06

Peter D. Gray (pdg(a)uow.edu.au) has sent you a news article. (Email address has not been verified.) ------------------------------------------------------------ Personal message: Prayers held for Egyptian writer Mahfouz - Yahoo! News http://news.yahoo.com/s/ap/20060831/ap_en_ot/egypt_mahfouz ============================================================ Yahoo! News http://news.yahoo.com/

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RE: when to use minra ?
by Glenn Walker 31 Aug '06

31 Aug '06

Without going too crazy into technical detail (statit counters), the easiest way has been to look at sysstat output: if disk reads are significantly higher than net out or tape backup (depending on the workload - ie, no reconstructs or reallocates running), then you could probably use minra. That type of fingerprint signifies that the disks have more reads than necessary. Some are ok but too many will cause performance problems. Beyond this, you can look at the statit and wafl_susp counters to determine things about disk fragmentation and I/O and readahead cache (respectively). Glenn -----Original Message----- From: owner-toasters(a)mathworks.com [mailto:owner-toasters@mathworks.com] On Behalf Of Peter D. Gray Sent: Thursday, August 31, 2006 1:59 AM To: toasters(a)mathworks.com Subject: when to use minra ? Does anybody have recipes or suggestions on how to work out if turning on minra will improve or decrease performance? Are there counters you can query in ONTAP that are helpful? Regards, pdg -- See mail headers for contact information. sts more data from the same file, the data is already in the cache so the response is faster. However, if your file reading pattern is completely random, then minra off may result in extra disk reads that are wasted because the client never requests the extra data read from the disks. Your reading pattern may not be as random as you think, however, and it is very unusual for minra on to be helpful. I have seen one situation where minra on was a win. On a FAS960c clustered pair and we had FC LUNs. The clients were Solaris boxes running Veritas. For performance we used Veritas to stripe a pair of LUNs, one LUN from each filer. We built a Veritas filesystem on the striped LUNs. As you can imagine, this thoroughly scrambled up file data because it was striped over two filers, somewhat defeating the Netapp read ahead strategy. We were storing email on this striped filesystem and so we had a very heavy read load. With minra off disk reads in KB/sec were about 10% to 20% higher than FC writes, indicating that the extra reads were probably going to waste. I turned minra on and the disk reads dropped to a little less than the FC writes. We have since switched from FC LUNS to NFS mounted volumes and turned minra back off. Steve Losen scl(a)virginia.edu phone: 434-924-0640 University of Virginia ITC Unix Support

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when to use minra ?
by Peter D. Gray 31 Aug '06

31 Aug '06

Does anybody have recipes or suggestions on how to work out if turning on minra will improve or decrease performance? Are there counters you can query in ONTAP that are helpful? Regards, pdg -- See mail headers for contact information.

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netapp X2050B dual fibre adapter
by Mopar Guy 23 Aug '06

23 Aug '06

have an extra one of these and was wondering if anyone on this list could use one. email offers, thanks.

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