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Fix typos (#33)

pull/35/head
Yadong Wen 2017-03-23 22:42:02 -04:00 committed by Donne Martin
parent 0c8be40660
commit 3021a3aed3
1 changed files with 2 additions and 2 deletions
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@ -1218,7 +1218,7 @@ Write-through is a slow overall operation due to the write operation, but subseq
<i><a href=http://www.slideshare.net/jboner/scalability-availability-stability-patterns/>Source: Scalability, availability, stability, patterns</a></i>
</p>
In write-behind, tha application does the following:
In write-behind, the application does the following:
* Add/update entry in cache
* Asynchronously write entry to the data store, improving write performance
@ -1348,7 +1348,7 @@ TCP is a connection-oriented protocol over an [IP network](https://en.wikipedia.
* Sequence numbers and [checksum fields](https://en.wikipedia.org/wiki/Transmission_Control_Protocol#Checksum_computation) for each packet
* [Acknowledgement](https://en.wikipedia.org/wiki/Acknowledgement_(data_networks)) packets and automatic retransmission
If the sender does not receive a correct response, it will resend the packets. If there are multiple timeouts, the connection is dropped. TCP also implements [flow control](https://en.wikipedia.org/wiki/Flow_control_(data)) and [congestion control](https://en.wikipedia.org/wiki/Network_congestion#Congestion_control). These guarantees cause delays and generally results in less efficient transmission than UDP.
If the sender does not receive a correct response, it will resend the packets. If there are multiple timeouts, the connection is dropped. TCP also implements [flow control](https://en.wikipedia.org/wiki/Flow_control_(data)) and [congestion control](https://en.wikipedia.org/wiki/Network_congestion#Congestion_control). These guarantees cause delays and generally result in less efficient transmission than UDP.
To ensure high throughput, web servers can keep a large number of TCP connections open, resulting in high memory usage. It can be expensive to have a large number of open connections between web server threads and say, a [memcached](#memcached) server. [Connection pooling](https://en.wikipedia.org/wiki/Connection_pool) can help in addition to switching to UDP where applicable.