ImmutableDB: allow reading concurrently with appending #1907
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Read the potentially stale value of the internal state provided by the `StrictMVar` instead of blocking on the `TMVar` in case an appender has locked it. Reads can safely happen concurrently with appends, so this will allow for some more concurrency. I don't expect this to make any impact for a "client" node that is syncing, as it will typically not read from its ImmutableDB, only append to it, which is necessarily sequential. However, a "server" node might have to read headers/blocks from its ImmutableDB to serve to other nodes. Serving multiple requests won't require taking + putting a `TMVar` anymore, it's just reading a `TVar` now. I expect to see the most improvement for a node serving others while it is also still syncing itself. Blocks being appended to the ImmutableDB will happen concurrently with all read requests.
edsko
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1900: Label mux threads r=karknu a=karknu 1907: ImmutableDB: allow reading concurrently with appending r=mrBliss a=mrBliss Read the potentially stale value of the internal state provided by the `StrictMVar` instead of blocking on the `TMVar` in case an appender has locked it. Reads can safely happen concurrently with appends, so this will allow for some more concurrency. I don't expect this to make any impact for a "client" node that is syncing, as it will typically not read from its ImmutableDB, only append to it, which is necessarily sequential. However, a "server" node might have to read headers/blocks from its ImmutableDB to serve to other nodes. Serving multiple requests won't require taking + putting a `TMVar` anymore, it's just reading a `TVar` now. I expect to see the most improvement for a node serving others while it is also still syncing itself. Blocks being appended to the ImmutableDB will happen concurrently with all read requests. Co-authored-by: Karl Knutsson <[email protected]> Co-authored-by: Thomas Winant <[email protected]>
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Read the potentially stale value of the internal state provided by the
StrictMVarinstead of blocking on theTMVarin case an appender has lockedit. Reads can safely happen concurrently with appends, so this will allow for
some more concurrency.
I don't expect this to make any impact for a "client" node that is syncing, as
it will typically not read from its ImmutableDB, only append to it, which is
necessarily sequential. However, a "server" node might have to read
headers/blocks from its ImmutableDB to serve to other nodes. Serving multiple
requests won't require taking + putting a
TMVaranymore, it's just reading aTVarnow.I expect to see the most improvement for a node serving others while it is
also still syncing itself. Blocks being appended to the ImmutableDB will
happen concurrently with all read requests.