Each OBServer node runs a single observer process. An observer process uses many threads, which can be divided into worker threads and background threads.
Tenant worker threads
A thread that processes SQL and transaction requests is referred to as a worker thread. Each tenant has its own worker threads.
Background threads
Tenant-specific background threads
An observer process contains the following tenant-specific background threads, and each tenant has a set of these threads:
disk io: the thread that processes disk I/O.
dag thread: the thread that performs tasks such as the minor compaction, major compaction, and migration of partitions.
clog writer: the thread that writes clogs.
election worker: the thread that is used for leader election.
misc timer: a set of background timer threads that are used to clear resources.
Non-tenant-specific background threads
An observer process contains the following non-tenant-specific background threads:
net io: the thread that processes the network I/O.
RootServer-dedicated threads.
