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MySQL – Steps to break down large time series data & queries (Part 2/2)

database1) Appends date time to the table name

For example, a table name is Data_Connections_History. Then the application appends the date at the end of table name, such as Data_Connections_History_2009_3_14. The application should be able to create these tables automatically and insert the new entries. Read more »


The future of homeplug networking

The use of electric wiring as a mean of networking is a significant movement in terms of connectivity. In the future homeplugs will replace wireless networking and much of the ethernet cabling in homes or home offices. Read more »


MySQL – Steps to break down large time series data & queries (Part 1/2)

 databaseIn my previous article, I have experimented and optimized query using range data. In this article, I will discuss two approaches to improve the scalability and the performance of continuous large time series data. The scalability is achieved by first separating the time series data into multiple tables in fixed time span and the performance (also scalability) is improved by breaking a long range query into multiple short fix time range queries to take advantage of the query cache. In fact, this is quite a common approach on optimizing time series data. Read more »


A useful document for explaining interrupt throttling triggered by high network load

FreeBSDI was tuning network performance under high traffic load on FreeBSD and stumbled across some parameters on the em drivers for the Intel Gigabit Network Card. The man page of em(4) explains briefly what Read more »


Troubleshooting on usbmount – vfat filesystem is not supported by default

I have spent ages figuring out why on earth the auto mount of usb flash drive was not working on my Ubuntu installation (8.04 LTS). Somehow I kept thinking it was udev problem, kept trying to debug with udevadm. I also read some posts on Ubuntu forums saying that there is a currently a bug in auto mount pluggable usb devices. Read more »


Making the most of unix commands when programming (Part 2) – the awk command

unixAwk command is one of the most useful unix tools and yet the most (in my view) underrated. It can save you a lot of efforts writing any code.  Everyone uses a lot of grep in conjunction with programming but awk can do more than grep in some cases. Read more »