Low-Overhead Dynamic Instruction Mix Generation using Hybrid Basic Block Profiling

Dynamic instruction mixes form an important part of the toolkits of performance tuners, compiler writers, and CPU architects. Instruction mixes are traditionally generated using software instrumentation, an accurate yet slow method, that is normally limited to user-mode code. We present a new method for generating instruction mixes using the Performance Monitoring Unit (PMU) of the CPU. It has very low overhead, extends coverage to kernel-mode execution, and causes only a very modest decrease in accuracy, compared to software instrumentation. In order to achieve this level of accuracy, we develop a new PMU-based data collection method, Hybrid Basic Block Profiling (HBBP). HBBP uses simple machine learning techniques to choose, on a per basic block basis, between data from two conventional sampling methods, Event Based Sampling (EBS) and Last Branch Records (LBR). We implement a profiling tool based on HBBP, and we report on experiments with the industry standard SPEC CPU2006 suite, as well as with two large-scale scientific codes. We observe an improvement in runtime compared to software instrumentation of up to 76x on the tested benchmarks, reducing wait times from hours to minutes. Instruction attribution errors average 2.1%. The results indicate that HBBP provides a favorable tradeoff between accuracy and speed, making it a suitable candidate for use in production environments

The diet of the human groups buried in a late- and post-Medieval rural parish cemetery in Libkovice (Czech Republic)

Libkovice is a village in the northwestern Czech Republic that was demolished at the end of the last century due to the expansion of a nearby mine. The former church cemetery has been a subject to bioarchaeological excavation and research, where some 850 burials from the 13th to the 19th Century have been discovered so far. With the application of stable isotope analysis, it has also been possible to uncover the dietary patterns of this exemplary rural Central European community, which was the aim of this study.The materials analysed here consist of samples from long bones of 56 burials and 18 animal bones discovered in Libkovice during the 2019/21 excavations. It has been employed stable carbon (δ13C) isotope analysis to determine the average contributions of foods derived from the C3 plants.Statistically significant differences were found between the analyzed fauna and human samples for nitrogen (F=47.4 p<0.05) and carbon (F=19.18 p<0.05). There were no statistically significant differences in the analyzed animal and human samples between the specify centuries. When considering the ages of various human individuals, the results indicated statistically significant differences in nitrogen isotopes (F= 7.71 p<0.05) between children from the infants I group and older children together with adults from the Middle Ages, as well as between children from the infants I group and adults (F= 3.3, p<0.05) from the modern times. The proportion of food from C3 plants that made up the diets of the studied population was on average 89%, and the potential proportion of freshwater fish in the diet could be higher than 80%.The similarity between the chronologically diverse groups may indicate similar strategies for food acquisition. The results obtained for the population of Libkovice are very similar to the diets of the populations living in Central Europe broadly during the two periods

Diagenetic signals from ancient human remains : bioarchaeological applications

This preliminary study examines the potential effects of diagenetic processes on the oxygen-isotope ratios of bone and tooth phosphate (δ18O) from skeletal material of individuals representing the Corded Ware Culture (2500–2400 BC) discovered in Malżyce (Southern Poland). Intra-individual variability of Ca/P, CI, C/P, collagen content (%) and oxygen isotopes was observed through analysis of enamel, dentin and postcranial bones. Using a variety of analytical techniques, it was found that, despite the lack of differences in soil acidity, not all the parts of a skeleton on a given site had been equally exposed to diagenetic post mortem changes. In a few cases, qualitative changes in the FTIR spectrum of analysed bones were observed. The data suggest that apart from quantitative analyses, i.e., the calculation of Ca/P, CI, C/P and collagen content, qualitative analyses such as examination of the absorbance line are recommended. The degree to which a sample is, contaminated on the basis of any additional, non-biogenic peaks, deemed to be contaminated should also be specified

Konstrukcje wybranych środowisk dedykowanych do obliczeń rozproszonych

In this paper two technologies for distributed computations are presented – Apache Hadoop and XtreemOS. The first of them is widely used for web services. Its main purpose is an analysis of large data. The second one is developed to distribute tasks between cluster nodes regarding the available resources. This technologies differ in construction context, which should be considered when applied.W pracy tej zostały przedstawione dwie technologie do obliczeń rozproszonych – Apache Hadoop oraz XtreemOS. Pierwsza z nich jest szeroko stosowana dla usług sieciowych i internetowych. Druga technologia oferuje możliwość rozsyłania zadań pomiędzy węzły klastra, z uwzględnieniem wymaganych zasobów. Technologie te różnią się budową, co powinno być uwzględnione podczas wyboru dla danego problemu obliczeniowego oraz podczas implementacji

Od pamięci biodziedzicznej do postpamięci

Na tom niniejszy składają się teksty powstałe w oparciu o trojakie spotkania: pierwszy rodzaj stanowiły wykłady prowadzone przez zaproszonych gości, reprezentujących różne dziedziny czy pola badawcze, które w pewnym niezbędnym uproszczeniu podzielić można na historiografię (Ewa Domańska), filozofię (Agata Bielik-Robson), literaturoznawstwo i studia nad pamięcią (Michael Rothberg), filozofię literatury (Michał Paweł Markowski). Wykładom towarzyszyły warsztaty, których prowadzący przedstawiają swoje teksty w części drugiej, a na część trzecią składają się zapisy wystąpień panelowych. Tego typu sesje zajęciowe siłą rzeczy odznaczają się zarówno sporą intensywnością (różnego rodzaju spotkania od rana do wieczora), jak i nieuniknioną rozmaitością spojrzenia, co zresztą stanowi jeden z ogromnych plusów podobnych przedsięwzięć. Kolejnym jest nieco bardziej „personalistyczne” zetknięcie się nie tyle z tekstem, co z postacią autora, a zatem i z osobowością badacza. Klamrą spinającą wszystkie wydarzenia stała się pamięć, bardzo różnie pojmowana i traktowana, a owa różnorodność punktów wyjścia i spojrzeń na formy oraz miejsca funkcjonowania pamięci przerodziła się w bogactwo doświadczeń „nadawców” oraz obfitość doznań (także tych odciskających się w pamięci) „odbiorców”.This volume comprises texts created on the basis of three-fold meetings: the first kind were constituted by lectures led by invited guests, representing various fields and areas of research, which, in some necessary simplification, can be divided into historiography (Ewa Domańska), philosophy (Agata Bielik-Robson), literary and memory studies (Michael Rothberg), and philosophy of literature (Michał Paweł Markowski). The lectures were accompanied by workshops, whose leaders present their texts in the second part of the work, and the third part is made up of notes from panel talks. As per the nature of these types of sessions, they present themselves as highly intense (various meetings from morning until evening), as well as showing the unavoidable variety in outlooks, which is one of the major advantages of such events. Another advantage is a slightly more ‘personalist’ encounter, not so much with text, but with the figure of an author, and thus also with the personality of a researcher. What became the idea bringing all these activities together was memory, understood and treated in very different ways. The variety of starting points and views on the forms and places of the functioning of memory then transformed itself into an abundance of experiences of the ‘originators’ and the richness of feelings (also of those imprinting themselves in memory) of the ‘receivers’

Quantification of Gleason Pattern 4 at MRI-Guided Biopsy to Predict Adverse Pathology at Radical Prostatectomy in Intermediate-Risk Prostate Cancer Patients

Background: Data on Gleason pattern 4 (GP4) amount in biopsy tissue is important for prostate cancer (PC) risk assessment. We aim to investigate which GP4 quantification method predicts adverse pathology (AP) at radical prostatectomy (RP) the best in men diagnosed with intermediate-risk (IR) PC at magnetic resonance imaging (MRI)-guided biopsy. Methods: We retrospectively included 123 patients diagnosed with IR PC (prostate-specific antigen <20 ng/mL, grade group (GG) 2 or 3, no iT3 on MRI) at MRI-guided biopsy, who underwent RP. Twelve GP4 amount-related parameters were developed, based on GP4 quantification method (absolute, relative to core, or cancer length) and site (overall, targeted, systematic biopsy, or worst specimen). Additionally, we calculated PV×GP4 (prostate volume × GP4 relative to core length in overall biopsy), aiming to represent the total GP4 volume in the prostate. The associations of GP4 with AP (GG ≥ 4, ≥pT3a, or pN1) were investigated. Results: AP was reported in 39 (31.7%) of patients. GP4 relative to cancer length was not associated with AP. Of the 12 parameters, the highest ROC AUC value was seen for GP4 relative to core length in overall biopsy (0.65). an even higher AUC value was noted for PV × GP4 (0.67), with a negative predictive value of 82.8% at the optimal threshold. Conclusions: The lack of an association of GP4 relative to cancer length with AP, contrasted with the better performance of other parameters, indicates directions for future research on PC risk stratification to accurately identify patients who may not require immediate treatment. Incorporating formulas aimed at GP4 volume assessment may lead to obtaining models with the best discrimination ability