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--- pfsense:squid:optimizing_squid [2020/03/22 18:10] – [Test your disk speed] peter
+++ pfsense:squid:optimizing_squid [2020/04/09 13:13] (current) – removed peter
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-====== PFSense - Squid - Optimizing Squid ======
-For the most part, Squid is quite dynamic in handling varying loads but there are some key things to consider.
-The most performance affecting attribute about Squid is the cache itself.
-If the cache is located on a slow device then the performance of all content will be dependent on this limitation.
-For this reason, it is advised that you run your cache on the fastest Read/Write medium that you can.
-If your disk is performing other Read/Write operations it can slow the performance of surfing the net.
-Another thing to consider is this; the cache is particularly useful when bandwidth is slow or expensive because it can prevent the repetitive download of data, but if your network speed exceeds the I/O performance of your cache media, it will slow the experience down. In cases where network speed exceeds cache-disk I/O, some people run Squid cacheless.
-----
-===== Cacheless =====
-This is useful if the performance of your cache disk is outstripped by the bandwidth of your ISP.
-There may be slowness in your proxy server as a result of the cache not being able to write fast enough to disk.
-==== Test your disk speed ====
-Ensure that you have sufficient space in the directory of your cache (/var/spool/squid).
-You will need just over 10GB of space to do this test (or you can change the test to do a smaller amount).
-<code bash>
-df -h
-</code>
-It is best to perform this test when the usage is low. Perform the following write test:
-<code bash>
-dd if=/dev/zero of=/var/spool/squid/10GB bs=1024 count=10240000 && rm -rf /var/spool/squid/10GB
-</code>
-You should get results similar to this:
-<code bash>
-10240000+0 records in
-10240000+0 records out
-10485760000 bytes (10 GB) copied, 84.292 s, 124 MB/s
-</code>
-The results will show the write speed of data to your directory.
-If the speed of the internet at your location outstrips the ability to write data in the cache, you may need to set up a no-cache option.
-As a typical rule of thumb, your cache to bandwidth ratio needs to perform at a factor of 16:1.
-For example, if your disk speed is 100MB/s (800Mb/s) you can perform well with a 50Mb/s pipe.
-If you have a 100Mb/s pipe, your disk performance must exceed 200MB/s.
-In this example, the drive performs at 124 MB/s which means that it should be sufficient for a 62 Mb/s ISP download pipe.
-<WRAP info>
-**NOTE:**  Please note that these are approximations designed for simple planning.
-</WRAP>
-----
-===== Speed things up =====
-There are multiple ways on speeding up your cache.
-You could use a faster drive like an SSD.
-You could use multiple drives (like RAID 0 or RAID 10).
-Caching is really designed to conserve bandwidth but in situations where the bandwidth exceeds your disk performance, you can just turn off the cache.
-This does NOT affect reports so it can be a real win in high bandwidth situations.
-To remove the cache you need to change a setting:
-|Maximum Object Size|0|
-|Maximum Object Size in RAM|0|
-Remember to restart Squid for this to take effect.
-----
-===== Add more Subnets =====
-Squid usually uses the LAN subnets of your network.
-To add addition lans, add additional CIDR subnets, to **Allowed Subnets** on the **ACL** tab.
-For example to add the networks of 10.1.1.0, 10.1.4.0, 10.1.5.0, 10.1.6.0, 10.1.7.0:
-<code>
-.1.1.0/24 10.1.4.0/22
-</code>
-Remember to restart Squid for this to take effect.