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Single-core memory bandwidth: Latency, Bandwidth, and Concurrency

John McCalpin

Latency” is the duration from the execution of a load instruction (to an address that misses in all the caches), and the completion of that load instruction when the data is returned from memory. The example below is for a 2005-era processor with 60 ns memory latency and 6.4 cache lines -> 5.6

Latency 71
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Observability platform vs. observability tools

Dynatrace

Metrics are measures of critical system values, such as CPU utilization or average write latency to persistent storage. For example, in 2005, Dynatrace introduced a distributed tracing tool that allowed developers to implement local tracing and debugging. Observability is made up of three key pillars: metrics, logs, and traces.

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Single-core memory bandwidth: Latency, Bandwidth, and Concurrency

John McCalpin

Latency” is the duration from the execution of a load instruction (to an address that misses in all the caches), and the completion of that load instruction when the data is returned from memory. The example below is for a 2005-era processor with 60 ns memory latency and 6.4 cache lines -> 5.6

Latency 40
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Linux Load Averages: Solving the Mystery

Brendan Gregg

The oldest change in the entire Linux repo dates back to 2005, when Linus imported Linux 2.6.12-rc2, Some people have found values that seem to work for their systems and workloads: they know that when load goes over X, application latency is high and customers start complaining. Latency was acceptable and no one complained.

Latency 111
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Deprecated features to take out of your toolbox – Part 1

SQL Performance

The system table sys.sysprocesses was replaced way back in SQL Server 2005 by a set of dynamic management views (DMVs), most notably sys.dm_exec_requests , sys.dm_exec_sessions , and sys.dm_exec_connections. Recently one of our teams was investigating a log reader latency issue.

Latency 57
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The Surprising Effectiveness of Non-Overlapping, Sensitivity-Based Performance Models

John McCalpin

The presentation discusses a family of simple performance models that I developed over the last 20 years — originally in support of processor and system design at SGI (1996-1999), IBM (1999-2005), and AMD (2006-2008), but more recently in support of system procurements at The Texas Advanced Computing Center (TACC) (2009-present).

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The Surprising Effectiveness of Non-Overlapping, Sensitivity-Based Performance Models

John McCalpin

The presentation discusses a family of simple performance models that I developed over the last 20 years — originally in support of processor and system design at SGI (1996-1999), IBM (1999-2005), and AMD (2006-2008), but more recently in support of system procurements at The Texas Advanced Computing Center (TACC) (2009-present).