tag:blogger.com,1999:blog-15440695.comments2024-02-29T10:39:57.857-05:00Alex Fatkulin's BlogAlex Fatkulinhttp://www.blogger.com/profile/06361288475877100451noreply@blogger.comBlogger177125tag:blogger.com,1999:blog-15440695.post-25963382390055213482018-01-31T18:26:46.006-05:002018-01-31T18:26:46.006-05:00Superb blog. Interestingly the keys imported into ...Superb blog. Interestingly the keys imported into the PDB don't appear in v$encrypted_keys until you run the "ADMINISTER KEY MANAGEMENT USE KEY ..." command in the PDB as per MOS 1678525.1, but even then, this is lost on the next PDB startup.Anonymoushttps://www.blogger.com/profile/16289688923958744447noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-56053024025305174742017-07-16T09:14:25.008-04:002017-07-16T09:14:25.008-04:00Excellent evaluation. We are certainly seeing a mu...Excellent evaluation. We are certainly seeing a much larger impact of cell single block reads on performance since moving to 12c.Mike Eubanksnoreply@blogger.comtag:blogger.com,1999:blog-15440695.post-37427290674398657552017-05-31T10:11:17.594-04:002017-05-31T10:11:17.594-04:00Thanks for your comment. I think comparing M7 thre...Thanks for your comment. I think comparing M7 threads to E5 cores is still a good comparison because:<br /><br />1. It shows that M7 still have a single threaded performance deficit. There is a class of applications/tasks that care about it.<br /><br />2. If I have a query running with a certain DOP on Intel and run the same query with the same DOP on M7 I shouldn't be surprised if I get much slower performance (assuming CPU-bound case). Hopefully this blog post will prevent some other people from having a "bad surprise". DOPs will likely have to be increased for such queries (potentially bringing more concurrency issues?).<br /><br />3. Would you rather have M7 with 4 threads per core where each thread is twice as fast?<br /><br />4. Why can't we compare 22 E5 cores vs 22 M7 cores where both are running 22 threads? Well that's because such a case renders M7 useless ;-) All the while it's a valid use case for Intel -- Azure runs with HT disabled, for instance. Food for thought.Alex Fatkulinhttps://www.blogger.com/profile/06361288475877100451noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-67524917894268393562017-05-31T08:54:58.348-04:002017-05-31T08:54:58.348-04:00Hi Alex,
I can confirm that single-threaded perfor...Hi Alex,<br />I can confirm that single-threaded performance of SPARC M7 core is worse than Intel x86-64 core<br />it was bad surprise that hash joins perform longer after moving from x86-64 to SuperCluster....<br />BTW:<br />good comparison would be to compare core-by-core performance - actually price based performance if we consider core factor table.<br />so <br />22 cores(44 threads) of E5-2699V4<br />vs<br />22 cores(176 threads) of SPARC M7<br />?odenysenkohttps://www.blogger.com/profile/13962845912456085125noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-91615094612164639752017-05-25T10:36:07.500-04:002017-05-25T10:36:07.500-04:00This was a LIO test so the entire test was done in...This was a LIO test so the entire test was done in-memory (buffer cache).Alex Fatkulinhttps://www.blogger.com/profile/06361288475877100451noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-62661316867950448522017-05-25T09:36:46.213-04:002017-05-25T09:36:46.213-04:00Hello, Alex !
What the storage equipment did you ...Hello, Alex !<br /><br />What the storage equipment did you use for the tests ? Thank youpanzer.hierhttps://www.blogger.com/profile/16150395032367802483noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-91113272829468362592017-05-24T09:42:42.081-04:002017-05-24T09:42:42.081-04:00Well, I guess I didn't understand what you'...Well, I guess I didn't understand what you're trying to prove here? If you are trying to compare SPARC M7 to Intel's E5-2699 V4, I would think you'd want to compare both architectures at its limits? And of course, licensing, licensing costs most likely will be the biggest consideration in comparing these two and as licensing is mostly per core based, comparing performance core vs core most likely what most readers would be interested in. Im certainly interested ;-)Anonymoushttps://www.blogger.com/profile/01548704524448863996noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-31759179698511725882017-05-24T09:36:50.125-04:002017-05-24T09:36:50.125-04:00Hello Phil,
thank you for your comment. The way y...Hello Phil,<br /><br />thank you for your comment. The way you posed the question seems to indicate that you find this comparison unfair. Which by the way I do too :) Assuming we agree on this I also think that comparing a chip with 256 threads to a chip with 44 threads in a way that benefits highly threaded architecture is unfair as well.Alex Fatkulinhttps://www.blogger.com/profile/06361288475877100451noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-86080007341366329082017-05-24T09:11:48.214-04:002017-05-24T09:11:48.214-04:00Why are you comparing SPARC M7 thread performance ...Why are you comparing SPARC M7 thread performance to Intel E5-2699 V4 core performance? A single SPARC M7 chip has 32 x cores and 256 x threads versus Intel E5-2699 V4 @ 22 x cores, 44-threads, almost 6x fewer threads! Why not compare core to core performance or atleast run 88-threads to max out the Intel 2-socket box to see how the SPARC M7 would compare?Anonymoushttps://www.blogger.com/profile/01548704524448863996noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-69223107546150825942016-11-07T09:04:41.858-05:002016-11-07T09:04:41.858-05:00The System I/O, with rare exceptions, is done by t...The System I/O, with rare exceptions, is done by the background processes. Since the query displays foreground events (the same way AWR does) it excludes it.Alex Fatkulinhttps://www.blogger.com/profile/06361288475877100451noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-31939926069991369152016-11-04T09:24:10.300-04:002016-11-04T09:24:10.300-04:00Nice query. Why are you excluding the 'System ...Nice query. Why are you excluding the 'System I/O' wait class and not just the 'Idle' one ?<br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-15440695.post-42855150121105127832016-05-24T13:55:38.972-04:002016-05-24T13:55:38.972-04:00I had the same error message where I had 3 disks o...I had the same error message where I had 3 disks of 100GB in a Disk Group and required to add 3 additional disks of 50GB each to this diskgroup of 3*100Gb.<br />I tried the following steps to make it work.<br /><br />Steps:<br />1) Resized the disks in the Disk group to match the 3 additional disks I need to add to this group at the MB level and not GB level since it was throwing an error message if the size in MB did not match exactly.<br />2) Added the 3 additional disks without any error.<br /><br />Oracle12chttps://www.blogger.com/profile/10641347695194782211noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-25045733079464737112016-02-06T04:50:18.941-05:002016-02-06T04:50:18.941-05:00Hi ALex great job.
The fact that you found about ...Hi ALex great job.<br /><br />The fact that you found about 11gR2 is more aggressive and starts doing direct path read at _small_table_threshold vs _small_table_threshold *5 on 11gR1<br />is now considered as a bug .<br />See Bug 18498878 - SMALL TABLE DOES NOT CACHE PROPERLY AFTER UPGRADE TO 12.1<br /><br />The bug is present on 11.2.0.2, 11.2.0.3, 11.2.0.4 and 12.1 <br /><br />The bug do not affect 10gR2, 11.2.0.1 and 12.2 <br /><br />Regards,<br />ChrisAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-15440695.post-37687902874465669812016-02-05T01:12:33.949-05:002016-02-05T01:12:33.949-05:00interesting information. This is just the kind of ...interesting information. This is just the kind of information that i had been looking for, i'm already your rss reader now and i would regularly watch out for the new posts,Thanks a million once again, Regards<a href="www.traininghyderabad.in/2016/02/oracle-goldengate-training-in-hyderabad.html" rel="nofollow">oracle Goldengate training in hyderabad</a>, Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-15440695.post-63452308309726554592016-02-03T09:10:21.973-05:002016-02-03T09:10:21.973-05:00Hello,
yes you can use dblogreader if you do not ...Hello,<br /><br />yes you can use dblogreader if you do not have ASM.Alex Fatkulinhttps://www.blogger.com/profile/06361288475877100451noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-4556059023511796742016-02-03T02:23:34.478-05:002016-02-03T02:23:34.478-05:00Hi Alex,
Can DBLOGREADER be used with NON-ASM dat...Hi Alex,<br /><br />Can DBLOGREADER be used with NON-ASM databases?<br /><br />Regards,<br />NavinAnonymoushttps://www.blogger.com/profile/11918243146664117395noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-25709902132914827822015-09-15T12:04:06.136-04:002015-09-15T12:04:06.136-04:00Alex I really appreciate this post - just ran into...Alex I really appreciate this post - just ran into this on a clone from PROD to TEST - the TEST database did not work for sysdba for certain users and was writing the audit logs to a bizarre location. After unsetting the ORACLE_PATH it worked as expected again.Curt Swartzlandernoreply@blogger.comtag:blogger.com,1999:blog-15440695.post-72353179151529270012015-05-12T09:51:00.903-04:002015-05-12T09:51:00.903-04:00HLL is not precise. It's an estimation. count(...HLL is not precise. It's an estimation. count(distinct) gives you the exact value.Alex Fatkulinhttps://www.blogger.com/profile/06361288475877100451noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-45787350412819512242015-05-12T09:28:40.830-04:002015-05-12T09:28:40.830-04:00How come the number of distinct values is 753521 f...How come the number of distinct values is 753521 from the first query and 738105 from the second ?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-15440695.post-40374796903998077362015-03-12T21:22:11.790-04:002015-03-12T21:22:11.790-04:00Hi Jeremy,
in my tests both statements performed ...Hi Jeremy,<br /><br />in my tests both statements performed equivalently as far as this blog post is concerned allowing the datafile to be recovered and tablespace brought online. There seems to be no differences from this perspective.Alex Fatkulinhttps://www.blogger.com/profile/06361288475877100451noreply@blogger.comtag:blogger.com,1999:blog-15440695.post-81223631328901406662015-03-09T16:47:35.867-04:002015-03-09T16:47:35.867-04:00Hey Alex - I know this is an old post; but I think...Hey Alex - I know this is an old post; but I think my question would still be relevant. Do you know definitively if "offline drop" (undocumented afaik) is exactly the same as "offline for drop" (documented)? Or is there any difference in how Oracle might process these two statements?Jeremy Schneiderhttp://www.ardentperf.comnoreply@blogger.comtag:blogger.com,1999:blog-15440695.post-91594837434055687462015-01-15T20:59:28.557-05:002015-01-15T20:59:28.557-05:00Awesome, thanks a lotAwesome, thanks a lotAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-15440695.post-86018773183693663142015-01-13T09:20:53.400-05:002015-01-13T09:20:53.400-05:00Hi Alex. The fix for this issue is complete, so ex...Hi Alex. The fix for this issue is complete, so expect a patch to be available shortly. I'll post here when it's out.nigelbaylisshttp://www.oracle.comnoreply@blogger.comtag:blogger.com,1999:blog-15440695.post-49511125587068390402014-11-22T06:20:11.246-05:002014-11-22T06:20:11.246-05:00very good explanationvery good explanationAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-15440695.post-24829352390834205192014-10-24T03:42:07.948-04:002014-10-24T03:42:07.948-04:00Just a ping to keep you updated... Dev have a prop...Just a ping to keep you updated... Dev have a proposed fix. They are working on it, so it's "in the pipe".nigelbaylisshttp://www.oracle.comnoreply@blogger.com