Payday loan very quickly they often decide Emergency Payday Loans Emergency Payday Loans not refusing to new one.

Home > oracle > TX enqueue Mode 4的一点补充

TX enqueue Mode 4的一点补充

在06年的一篇blog TX lock中简略的解释了下TX enqueue的类型和对应的例子。

最近在数据库维护中又有了一点新的发现。

前面文章中提到Mode=4的TX lock又分为下面三种情况

* ITL entry数目不够
* Unique key的约束
* Bitmap index entry

再补充几种情况:

* Index block spilt
* Foreign key enforcement
* Alter tablespace … read only;
* Free Lists slot waits
* Possible with two phase commit
* Extent allocation slow in DMT tablespace

前面几种情况一些文档中多多少少有所提及,index block split较为常见。

最后一种extent allocation slow是实际中遇到的。在DMT的tablespace中,当free extent很多,但不满足分配条件时就会出现extent分配慢的情况,实际中分配一个extent需要8,9秒钟。从而导致大量的session wait在TX-4 enqueue上。

目前还没有找到文档有关于这个的相关说明,也许是因为DMT已经退出历史舞台了吧。

Eagle Fan oracle

  1. Eagle Fan
    April 28th, 2010 at 13:37 | #1

    再补充一点,对于IOT table,request type就是mod 4而不是mod 6

  2. May 24th, 2010 at 13:40 | #2

    很好,很强大

  3. June 2nd, 2011 at 19:53 | #3

    Do not use this medicine if you take selegiline capsules or tablets. ,

  4. April 17th, 2013 at 09:01 | #4

    I all the time used to read piece of writing
    in news papers but now as I am a user of net thus from now I am using net for articles
    or reviews, thanks to web.

  5. April 28th, 2013 at 08:37 | #5

    Today, taking into consideration the fast life style that everyone is having, credit cards get this amazing demand throughout the market. Persons from every field are using credit card and people who are not using the card have made up their minds to apply for one in particular. Thanks for expressing your ideas about credit cards.

  6. April 30th, 2013 at 21:02 | #6

    F*ckin’ tremendous things here. I am very happy to peer your post. Thanks a lot and i’m having a look forward to contact you. Will you kindly drop me a mail?

  7. May 6th, 2013 at 19:54 | #7

    hi!,I really like your writing very so much! percentage we communicate extra about your post on AOL? I need an expert in this house to unravel my problem. May be that’s you! Having a look forward to peer you.

  8. May 8th, 2013 at 19:17 | #8

    It is the best time to make a few plans for the long run and it is time to be happy. I’ve learn this publish and if I may just I want to counsel you few fascinating issues or suggestions. Perhaps you could write next articles referring to this article. I want to read even more issues approximately it!

  9. May 9th, 2013 at 09:52 | #9

    Its my fortune to visit at this website and find out my required post along with video demo, that’s YouTube video and its also in quality.

  10. May 13th, 2013 at 11:13 | #10

    I’ve been absent for a while, but now I remember why I used to love this web site. Thanks , I¡¦ll try and check back more frequently. How frequently you update your web site?

  11. May 14th, 2013 at 01:49 | #11

    I am not really certain if greatest practices have emerged close to things like that, but I’m sure that your great job is clearly identified. I was wondering if you offer any subscription to your RSS feeds as I will be very fascinated and can?t find any link to subscribe right here.

  12. May 14th, 2013 at 11:58 | #12

    I really feel other web-site lovers might look into this valuable website as a model. Especially clean and user-friendly approach, along with extremely good subject material! You’re very skilled when it comes to this important niche )

  13. May 14th, 2013 at 17:21 | #13

    Hi, Neat post. There’s a problem together with your website in internet explorer, would check this… IE still is the market chief and a big component to people will omit your great writing due to this problem.

  14. May 14th, 2013 at 22:32 | #14

    There’s noticeably a whole lot of dollars comprehend this. I assume you have produced particular good points in functions also.

  15. May 16th, 2013 at 02:40 | #15

    Hi! I’ve been reading your website to get a though now and lastly got the bravery to go ahead and provide you with a shout out from Kingwood Texas! Just wanted to mention retain up the wonderful job!

  16. May 16th, 2013 at 03:37 | #16

    hey there and thank you for the info – I have absolutely picked up anything new from proper right here. I did on the other hand expertise a couple of technical difficulties using this site, as I knowledgeable to reload the web site a lot of instances previous to I could get it to load correctly. I had been asking yourself in case your net host is OK? Not that I’m complaining, but slow loading instances instances will occasionally impact your placement in google and could damage your high-quality score if marketing and marketing and advertising with Adwords. Properly I am adding this RSS to my e-mail and may look out for a great deal far more of the respective fascinating content material. Make sure that you just update this again soon..

  17. May 18th, 2013 at 03:13 | #17

    I do trust all the ideas you’ve offered in your post. They are very convincing and will certainly work. Nonetheless, the posts are very short for novices. May you please extend them a little from next time? Thanks for the post.|

  18. May 23rd, 2013 at 17:36 | #18

    You’re so interesting! I don’t believe I’ve truly read something like this before. So good to discover somebody with some unique thoughts on this issue. Seriously.. thanks for starting this up. This site is something that is needed on the web, someone with a little originality!

  19. May 24th, 2013 at 11:11 | #19

    Websites we think you should visit… [...]although websites we backlink to below are considerably not related to ours, we feel they are actually worth a go through, so have a look[...]……

  1. No trackbacks yet.