Performance analysis of the Alpha 21264-based Compaq ES40 system
Bibliographic record
Abstract
This paper evaluates performance characteristics of the Compaq ES40 shared memory multiprocessor. The ES40 system contains up to four Alpha 21264 CPU's together with a high-performance memory system. We qualitatively describe architectural features included in the 21264 microprocessor and the surrounding system chipset. We further quantitatively show the performance effects of these features using benchmark results and profiling data collected from industry-standard commercial and technical workloads. The profile data includes basic performance information - such as instructions per cycle, branch mispredicts, and cache misses - as well as other data that specifically characterizes the 21264. Wherever possible, we compare and contrast the ES40 to the AlphaServer 4100 - a previous-generation Alpha system containing four Alpha 21164 microprocessors - to highlight the architectural advances in the ES40. We find that the Compaq ES40 often provides 2 to 3 times the performance of the AlphaServer 4100 at similar clock frequencies. We also find that the ES40 memory system has about five times the memory bandwidth of the 4100. These performance improvements come from numerous microprocessor and platform enhancements, including out-of-order execution, branch prediction, functional units, and the memory system.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.003 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".