WordPress: Network Transfer Speeds in Use
To determine why the bandwidth of the connection is important to a high-traffic site, let’s look at the math.
Assume your site receives 100,000 hits in a day. For the purpose of this computation, we will say that one “hit” is a single data transfer, whether that is a single file or a whole page and its supporting files. Averaged out, 100,000 hits in a day equates to 1.16 hits every second.
Also assume the average hit generates 160KB of transferred data; HTML, images, CSS, downloaded files, etc. Every second, your site is transferring 190KB of data (160KB/hit * 1.16 hits/s). The total, 190KB/s, equals about 1.5Mb/s of sustained throughput. (Note that KB = Kilobytes and Mb = Megabits. Most network speeds are rated in bits per second, whereas file sizes are measured in bytes.) Many network providers cap the transfer rate of a site to about this level; some higher, some lower. However, only if each user visits in a nice succession will this steady rate be maintained.
Usually, more than one user at a time will access your site. Sometimes during the day, nobody might access your site at all. If 10 people hit the site simultaneously per second, and that hit rate is sustained over a lengthy period — not uncommon for a high-traffic site — then you would need a 15Mb/s connection just to keep up with the simultaneous connections.
If your network adapters maximum theoretical speed is only 10Mb/s, your demand has already exceeded your capacity. WordPress had nothing to do with it.
It is not necessary to receive 100,000 hits to cause this problem. Sustaining this rate of connectivity for a mere hour generates only 36,000 hits. If visitors concentrate their access to a certain time of day (or an automated comment spam script attempts to access your system multiple concurrent times while posting comments) then you could be left with many dropped requests.
A 100Mb/s connection could handle up to 70 simultaneous connections at the same rate of download, but it is not likely that your network provider would offer the bandwidth that could fully use this speed without paying a premium. This is generally not something you can get with current shared hosting plans.
Tags: (Network, Averaged, bandwidth, computation, downloaded, high-traffic, purpose, speeds, sustained, transfer, transferred, Use, WordPress