In commit de38091827 the two IO priority classes streaming_read
and streaming_write into just one. The document docs/isolation.md
leaves a lot to be desired (hint, hint, to anyone reading this and
can write content!) but let's at least not have incorrect information
there.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20201101102220.2943159-1-nyh@scylladb.com>
Start a new document with an overview of isolation in Scylla, i.e.,
scheduling groups, I/O priority classes, controllers, etc.
As all documents in docs/, this is a document for developers (not users!)
who need to understand how isolation between different pieces of Scylla
(e.g., queries, compaction, repair, etc.) works, which scheduling groups
and I/O classes we have and why, etc.
The document is still very partial and includes a lot of TODOs on
places where the explanation needs to be expanded. In particular it
needs an accurate explanation (and not just a name) of what kind of
work is done under each of the groups and classes, and an explanation
of how we set up RPC to use which scheduling groups for the code it
executes.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Message-Id: <20190103183232.21348-1-nyh@scylladb.com>