Re: [bitfolk] Support this weekend / Ubuntu Lucid LTS releas…

er.<br>
<br>
SSD prices have now dropped enough that it&#39;s probably worth looking<br>
at how they can be used here. I can think of several ways to go:<br>
<br>
- Give you the option of purchasing SSD-backed capacity<br>
=A0=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D<br>
<br>
=A0Say SSD capacity costs 10 times what SATA capacity does. You get<br>
=A0to choose between 5G of SATA-backed storage or 0.5G of SSD-backed<br>
=A0storage for any additional storage you might like to purchase, the<br>
=A0same price for either.<br>
<br>
=A0Advantages:<br>
<br>
=A0- The space is yours alone; you get to put what you like on it. If<br>
=A0 =A0you&#39;ve determined where your storage hot spots are, you can put=
<br>
=A0 =A0them on SSD and know they&#39;re on SSD.<br>
<br>
=A0Disadvantages:<br>
<br>
=A0- In my experience most people do not appreciate choice, they just<br>
=A0 =A0want it to work.<br>
<br>
=A0 =A0Most people aren&#39;t in a position to analyse their storage use<b=
r>
=A0 =A0and find hot spots. They lack either the inclination or the<br>
=A0 =A0capability or both - the service is fine until it&#39;s not.<br>
<br>
=A0- It means buying two expensive SSDs that will spend most of their<br>
=A0 =A0time being unused.<br>
<br>
=A0 =A0Two required because they&#39;ll have to be in a RAID-1.<br>
<br>
=A0 =A0Most of the time unused because the capacity won&#39;t be sold<br>
=A0 =A0immediately.<br>
<br>
=A0 =A0Expensive because they will need to be large enough to cater to<br>
=A0 =A0as large a demand as I can imagine for each server.<br>
=A0 =A0Unfortunately I have a hard time guessing what that demand would<br=
>
=A0 =A0be like so I&#39;ll probably guess wrong.<br>
<br>
- Find some means of using SSDs as a form of tiered storage<br>
=A0=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D<br>
<br>
=A0We could continue deploying the majority of your storage from SATA<br>
=A0disks while also employing SSDs to cache these slower disks in<br>
=A0some manner.<br>
<br>
=A0The idea is that frequently-accessed data is backed on SSD whereas<br>
=A0data that is accessed less often is left on the larger-capacity<br>
=A0SATA, and *this remains transparent to the end user*, i.e. the VM.<br>
<br>
=A0This is not a new idea; plenty of storage hardware already does<br>
=A0it, ZFS can do it and so can BTRFS.<br>
<br>
=A0Advantages:<br>
<br>
=A0- For whatever benefit there is, everyone gets to feel it. If done<br>
=A0 =A0right, any VM that needs more IOPs should get more IOPs.<br>
<br>
=A0- Expensive SSDs purchased can be used immediately, in full.<br>
<br>
=A0Disadvantages:<br>
<br>
=A0- Since we can&#39;t use ZFS or expensive storage hardware, any<br>
=A0 =A0short-term solution is likely to be rather hacky. Do we want to<br>
=A0 =A0be pioneers here? This is your data.<br>
<br>
=A0- Customers with VMs that don&#39;t have heavy IO requirements (most)<b=
r>
=A0 =A0will be subsidising those who *do* have heavy IO requirements.<br>
=A0 =A0It&#39;s very unlikely we will put prices up, but SSDs are not free=
<br>
=A0 =A0so it has the effect of delaying the usual progression of<br>
=A0 =A0more-for-less that this type of service goes through.[1]<br>
<br>
=A0- Beyond what might be quite a blu