16 hours ago by Fenng

作者： Fenng 发布在 dbanotes.net. 如果有人问你一台 PC 服务器是否可以达到 99.99% 的高可用，该如何回答呢? 或许没有一台机器能"确保"达到这样的可用率，当然在某个时间段或许不会出问题，但这个肯定是看运气，而高可用基本上是没办法通过一台来达到目标的，我们更多的时候是设计方案确保在出问题的时候尽快接管故障机器，当然这要付出更大的成本。 对于 Oracle 的高可用方案可以参考 Maximum Availability Architecture (MAA) 白皮书，不过 Oracle 并不推崇操作系统级别的解决方案。MySQL 的指导策略倒是更为灵活一些，DRBD ® ...

DBA notes - dbanotes.net · Rank: 25,872 · 234 references

1 day ago by Andrew Ivanov

Очень часто, говоря про блейд-серверы или про виртуализацию, я сталкиваюсь с тем что собеседники ошибочно воспринимают эти технологии как средство объединения ресурсов нескольких физических серверов в один большой. Тогда как на самом деле, блейд-серверы это всего лишь удобным образом упакованные в о ...

Trinity, ... - blog.trinitygroup.ru · 2 references

18 days ago by Kaya

前面分析的主要是Exadata如何高效地进行计算。通过在存贮结点加入数据处理能力，Exdata不仅大大地提升了处理性能，而且解决了以前的Oracle架构上可能存在的CPU和网络的瓶颈问题。 一个Database Machine有8个DB节点，14个Cell (存贮)结点。在V1版本中，一个Cell可以提供1GB/s的带宽，14个Cell节点总共能提供的带宽为14GB/s。对于8个DB节点，每个节点都是两个CPU，每个CPU 4 个Cores。所以一个Database Machine中DB节点总共有64个Cores。 8 DB Nodes + 14 Cell Nodes = Balanced S ...

OS与Oracle - os2ora.com · 2 references

19 days ago by Kaya

下一个问题，Exadata如何解决CPU方面的瓶颈呢？ 在Exadata之前，我想无非两种思路，第一在原来节点上用更多更强的CPU，第二采用更多的RAC节点。 不过在Exadata的架构中，CPU的瓶颈已经从基本上得到很大的缓解，这就是存贮节点上CPU处理能力的介入。 还是以一个实际SQL为例: SELECT t0.id FROM (SELECT id FROM t0 WHERE id like '%54234245%' ) t0, (SELECT id FROM t1 WHERE id like '%54234245%' ) t1, (SELECT id FROM t2 WHERE id l ...

OS与Oracle - os2ora.com · 2 references

21 days ago by Kaya

Exadata应该说代表着Oracle Database未来的发展方向。这句话可不是一句广告词，依我看来，Exadata完全有这个资格享受这种待遇。 一个计算系统，最主要的是追求CPU，IO，Network之间的平衡。使这些计算资源能充分地发挥潜能。比如说，如果IO的扫描能力能达到10GB/s，如果存贮阵列到计算结点的带宽不能达到10GB/s，那么IO的扫描能力就不能得到充分发挥。又比如，如果CPU每秒钟只能处理6GB/s的数据量，10GB/s的IO扫描能力也不能能到充分发挥。 对一个计算系统另一个重要的衡量指标是如何有效地利用计算资源，这同样地包括CPU，IO，Network。比如说，虽然N ...

OS与Oracle - os2ora.com · 2 references

23 days ago by mubbisherahmed

My blog has been nominated for an award within the CIO/IT Director category, recommend my blog for the shortlisted candidates at: http://www.computerweekly.com/nominate.Voting for shortlisted entries will open on 27th October “If the only tool you have is a hammer, you tend to see every problem as a ...

Mubbisher Ahmed's IT Blog - mubbisherahmed.wordpress.com · 1 reference

26 days ago by kocakahin

As you all may know Voltaire is one of the most prominent IB technology vendors and investors had the partnership with Oracle in building Exadata Version 1. Yet another beautiful thing about Voltaire is that it is one of the companies invest on Open Source technologies and HPC (High Performance Comp ...

The great grandson of ... - husnusensoy.wordpress.com · Rank: 165,089 · 7 references

32 days ago by RandomDude

Some exciting news: InfiniBand has been added to the OpenStorage offerings starting with the Q3.2009. Check out Cindi's blog here. Of course, there have improvements for InfiniBand support in Solaris 10 10/09 release migrating over from the stuff in Nevada. I have been told the X4239A DDR FEM HCA is ...

Ted H. Kim's Weblog - blogs.sun.com/RandomDude

33 days ago by Douglas Eadline

Are clouds a good place to do build HPC Clusters? The use of virtualization and multi-core processors has made cloud computing an option for many users. The ability to buy cloud time as you need it and not purchase hardware is certainly attractive from a financial standpoint. The concept is not new ...

Cluster Connection - clusterconnection.com · 3 references

33 days ago by TMC Staff

TMC is now offering the high-performance optical 4x Infiniband DDR cables, with 20 Gbps data rates at distances up to 300 meters. The cables deliver the performance you need to build large, reliable computer clusters. With their low weight and bulk these high-performance active optical cables can re ...

TMC - SCSI Cables and More... - tmcscsi.com/blogger