当年科举，也不是谁都能进京赶考的吧！

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提供了 amd64/i386 平台 DVD安装盘ISO

有店铺卖家：105万+
活跃店铺： 85万+

季度交易额：188亿+
全年成交额：433亿+

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另: 支付宝用户规模参考数据

http://www.alleyinsider.com/2008/11/google-chrome-needs-add-ons

...PostgreSQL's query optimizer is smart, really smart and unless you have evidence otherwise you should trust what it is doing. In this particular case, the optimizer realizes that if a table has only a few rows that using the index is actually slower than just spinning through the entire table. Just because PostgreSQL isn't using your index today with a small number of rows, does not mean it won't choose to use it later when you have more data or the query changes...

PC-BSD 7 Released!

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[Q:] When using gjournal and for a gmirror volume, does the journal need to be mirrored as well to maintain redundancy? If so, when storing the journal on the same physical disks as the mirror, is it better to mirror at the slice level (journal and fs on different partitions in the same mirror) or at the partition level (journal and fs each have their own mirror) or does it matter?

[A:] The problem with mirroring each partition/slice separately is that when you have a crash, on boot, gmirror will start to rebuild all partitions at once, which may be problematic. On the other hand, when you mirror each partition/slice separately, and some partitions weren’t modified in last few seconds before the crash, gmirror will not resync them on boot, so not entire disk will be synchronized.

注：Gmirror如果对整个硬盘作镜像，系统崩溃重启后，gmirror将有较大可能需要自动重建所有分区(如果是1T HD，会是个大问题)。
如果对每个分区单独做镜像，如果某些个镜像分区在崩溃前几秒钟没有发生修改/写操作的话，镜像状态不会降级损坏，gmirror 就不需要在重启后重建这个分区，（如果将需要频繁写入的分区划为小于20G的独立分区做镜像，就可以一定程度上绕开以上的问题）。

When you run gjournal on top of gmirror/graid3 there is no need for resync after a crash, so bascially all cons against mirroring the whole disks and against mirroring partitions are no longer true. Both configurations will work the same. In that case I’d suggest mirroring the whole disks, because when one of your disks dies, you may just replace it and be down with it. If you mirror partitions separately, you first have to create partitions and insert each of them into their mirrors, which is more complex than simple ‘gmirror insert foo newdisk’.

注： 如果在Gmirror上启用gjournal, 就可以很大程度上避免在崩溃重启后重新同步(?) 这种情况下，推荐对整个硬盘做mirror。

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[Q:] does a gjournal volume need to be fsck’ed after a crash? If not, will it just work (e.g. fsck -p sees that the filesystem is clean) or does it need to be disabled somehow?

[A:] Gjournaled file system has to be fscked, but only to handle orphaned files. Such fsck on multiterabyte provider takes seconds, not hours.

注：gjournal 系统同样需要fsck, 但是非常迅速。

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只有一个疑问，不支持模块化插件架构的设计，如何打败敌人？

• Gmirror - recovering from a failed HDD
• Adding gmirror to an existing installation

Key facts:

• It is of, by and for the community (you).
• At this event, all open-source databases are created equal. We’ll learn together and grow together.
  It’s a combination conference and hackathon.
• It’s free.
• It is Friday night Nov 14, 18:00 through Sun the 16th at 18:00 in Charlottesville, Virginia USA in a very cool location.
• The website, where all details will be posted: http://opensqlcamp.pbwiki.com/
• The mailing group, where details will be discussed, decided and arranged: http://groups.google.com/group/opensqlcamp
• Date, time and place are confirmed and will not change. You can make your travel plans now. There’s travel information on the wiki.
• We already have some great speakers who have offered to give great talks. These and other details will show up on the wiki as they’re finalized.
• Sponsors are needed. See the wiki.

two disks can be synchronized over a network link of any speed or reliability - it can be restarted and immediately begin where it left off, and the amount of bandwidth used can be controlled…

参考链接:
Hammer streaming
HAMMER Update 31-Jul-2008 - Streaming Mirroring on HEAD