Let’s start with a guess – what is the most CPU-heavy operation in Sitecore? Answer: Performance counters initialization: Yes, that’s right, those performance counters which are powered by OS and super fast. Although Sitecore counter init implementation does not look offensive (volatile read & interlocked), counters are everywhere (cache lookup / access / object creation):Continue reading “Reckless interlocked operations”
Category Archives: Investigation
Why should an upper limit exist for every saved bit
Case study: polluted reports shows how system can be polluted with dummy data. Saving data (even HTTP referer) without validation can contaminate system as well: The results show astonishing 28KB for storing single value: Next time you see Analytics shards worth 600 GB – recall this post.
Can configuration be trusted?
The story why a mechanism to verify configuration is important.
Unit testing in Sitecore
Why ‘Sitecore is not testable’ cliche is no longer actual.
Performance crime: concurrent collections misuse
The case study on how the harmless collection could silently cause system to work slower and remain undetected for ages.
Performance crime: config to kill performance
Would you as a developer allow a setting that can make system 15 550 times slower? I’ve received a few memory dumps with high CPU; each scavenges AccessResultCache: How big is the cache so that every snapshot contains the operation? Detecting cache size from the snapshot A ClrMD code snippet locates objects in Sitecore.Caching.Generics.Cache namespaceContinue reading “Performance crime: config to kill performance”
Performance crime: no respect for mainstream flow
How expensive a lack of respect to mainstream usage could be?
Performance crime: wrong size detection
The amount of memory cache can use is defined in config: That is needed to protect against disk thrashing – running out of physical RAM so that disk is used to power virtual memory (terribly slow). That is a big hazard in Azure WebApps – much less RAM compared to old-school big boxes. Sitecore keepsContinue reading “Performance crime: wrong size detection”
Sitecore Fast Queries: second life
Breeze in life into Sitecore Fast Queries.
Why a powerful mechanism is not applied in modern designs?
Performance crime: careless allocations
I was investigating Sitecore Aggregation case a time back and my attention was caught by GC Heap Allocation mentioning RequiresValidator in top 10: Combining all generic entries together leads to over 7% of total allocations making it second most expensive type application wide! Yes, all it does is check object is not null Yes, itContinue reading “Performance crime: careless allocations”
Making it run faster 