This commit implements partitioned unordered maps and makes it possible
to traverse such a map in parallel, allowing for more efficient use of
CPU resources.
The `CachedSLEs`, `TaggedCache`, and `KeyCache` classes make use of the
new functionality, which should improve performance.
The pathfinding engine requires pre-building large tables which is a
resource-intensive operation. Typically, one would not expect that a
server configured as a validator would also support pathfinding APIs
and so, building those tables by default wastes resources.
This commit, if merged, will disable pathfinding on servers that are
configured as validators, unless the server operator opts to support
it explicitly, by configuring the `[path_search_max]` parameter.
Validator operators that wish to support pathfinding on a validator
and want to use the default values can add the following stanza to
their server's configuration file:
[path_search_max]
7
The priority of different types of jobs was set back in the early
days of development, based on insight and observations that don't
necessarily apply any longer.
Specifically, job types used by the server to sync to the network
were being treated as lower priority than client requests, making
it more difficult to regain sync.
This commit adjusts the priority of several jobs and should allow
servers to prioritize resynchronizing to the network over serving
clients.
The existing calculation would limit the maximum number of threads
that would be created by default to at most 6; this may have been
reasonable a few years ago, but given both the load on the network
as of today and the increase in the number of CPU cores, the value
should be revisited.
This commit, if merged, changes the default calculation for nodes
that are configured as `large` or `huge` to allow for up to twelve
threads.
The "sweep interval" is the amount of time between successive sweeps of
of various in-memory data structures to remove stale items.
Prior to this commit, the interval was automatically adjusted, based on
the value of the `[node_size]` option in a server's configuration file.
If merged, this commit introduces a new configuration option that makes
it possible for a server operator to adjust the sweep interval and make
a CPU/memory tradeoff:
[sweep_interval]
<integer>
The specified value represents the number of seconds between successive
sweeps. The range of valid values is between 10 and 600.
Important operator notes:
This is an advanced configuration option that should not be used unless
there is empirical data which suggests that the default sweep frequency
is either resulting in performance problems or is causing undue load to
the server.
Note that adjusting the sweep interval may not have the intended effect
on the server. Lower values will not always translate to a reduction of
memory usage and higher values will not always translate to a reduction
of CPU usage and/or load.
The performance characteristics of `std::unordered_map` are better
than `std::map` and the former should be preferred when the strict
ordering of the latter is not required.
* Only require adding the new feature names in one place. (Also need to
increment a counter, but a check on startup will catch that.)
* Allows rippled to have the code to support a given amendment, but
not vote for it by default. This allows the amendment to be enabled in
a future version without necessarily amendment blocking these older
versions.
* The default vote is carried with the amendment name in the list of
supported amendments.
* The amendment table is constructed with the amendment and default
vote.
* Also clean up some formatting in the Windows instructions
* Changed the recommended version for Windows to 1.1.1L after deeper
checking uncovered some build issues.
* Patch the soci unsigned-types.h file. If no changes are made, delete
the patched file and exit. If there are changes, backup the original
and replace it with the patched file.
* Fixes#3885
Patch Rocksdb only once:
* The repeated patches do not appear to affect build times, but avoiding
unnecessary copies is good for its own sake.
There are two mutexes in ValidatorSite: `site_mutex_` and `state_mutex_`. Some
function end up locking both mutexes. However, depending on the call, the
mutexes could be locked in different orders, resulting in deadlocks.
If both mutexes are locked, this patch always locks the `sites_mutex_` first.
The existing logic involves every server sending every transaction
that it receives to all its peers (except the one that it received
a transaction from).
This commit instead uses a randomized algorithm, where a node will
randomly select peers to relay a given transaction to, caching the
list of transaction hashes that are not relayed and forwading them
to peers once every second. Peers can then determine whether there
are transactions that they have not seen and can request them from
the node which has them.
It is expected that this feature will further reduce the bandwidth
needed to operate a server.
The existing license file contains copyright statements and license
snippets referencing code that has long since been removed from the
codebase and which are not necessary any longer.
The general copyright statement for the ISC License is also changed
from "Ripple Labs" which is one contributor to the codebase, to the
more general "XRP Ledger Developers".
Remaining code which was originally taken from Bitcoin includes the
relevant copyright statement(s) inline.
To aid in the automated detection of the license type by GitHub and
tools like `licensee`, the following statement which referenced the
ISC license, and which was listed at the bottom of the file, is now
incorporated at the top:
>The accompanying files incorporate work covered by the following copyright
>and previous license notice:
>
>Copyright (c) 2011 Arthur Britto, David Schwartz, Jed McCaleb,
>Vinnie Falco, Bob Way, Eric Lombrozo, Nikolaos D. Bougalis, Howard Hinnant
