As part of the GCC developers‘ on-demand range work for GCC 10, I’ve been playing with improving the backward jump threader so it can thread paths that are range-dependent. This, in turn, had me looking at the jump threader, which is a part of the compiler I’ve been carefully avoiding for years. If, like me, you’re curious about compiler optimizations, but are jump-threading-agnostic, perhaps you’ll be interested in this short introduction.
Continue reading “A gentle introduction to jump threading optimizations”
Open vSwitch (OVS) can use the kernel datapath or the userspace datapath. There are interesting developments in the kernel datapath using hardware offloading through the TC Flower packet classifier, but in this article, the focus will be on the userspace datapath accelerated with the Data Plane Development Kit (DPDK) and its new feature—partial flow hardware offloading—to accelerate the virtual switch even more.
This article explains how the virtual switch worked before versus now and why the new feature can potentially save resources while improving the packet processing rate.
Continue reading “Speeding up Open vSwitch with partial hardware offloading”
This article describes how to configure MongoDB’s WiredTiger memory cache in Red Hat Mobile Application Platform (RHMAP) to prevent high-usage memory issues and Nagios alerts. If the WiredTiger cache consumes all the memory available for a container, memory issues and Nagios alerts will occur.
The WiredTiger storage engine is the default storage engine starting in MongoDB version 3.2. It uses MultiVersion Concurrency Control (MVCC) architecture for write operations in order to allow multiple different modifications to the same document at the same time.
WiredTiger also caches data and creates checkpoints to give you the ability to recover anytime it’s necessary. For example, if a MongoDB image deployed in a container fails, it is useful to recover the data that was not persisted. Additionally, WiredTiger can recover un-checkpointed data with its journal files. See the journal documentation and snapshots and checkpoint documentation for more information.
Continue reading “Configuring the MongoDB WiredTiger memory cache for RHMAP”
This blog post is about my work to improve CRuby performance by introducing new virtual machine instructions and a JIT. It is loosely based on my presentation at RubyKaigi 2017 in Hiroshima, Japan.
As many Ruby people know, the author of Ruby, Yukihiro Matsumoto (Matz), set up a very ambitious goal for performance of CRuby version 3. Version 3 should be 3 times faster than version 2.
Koichi Sasada did a great job improving the performance of CRuby version 2 by about 3 times over version 1, by introducing a byte code virtual machine (VM). So I guess it is symbolic to set up the same goal for CRuby version 3.
Continue reading “Towards The Ruby 3×3 Performance Goal”