Demystifying the Performance of Data Transfers in High-Performance Research Networks

High-speed research networks are built to meet the ever-increasing needs of data-intensive distributed workflows. However, data transfers in these networks often fail to attain the promised transfer rates for several reasons, including I/O and network interference, server misconfigurations, and network anomalies. Although understanding the root causes of performance issues is critical to mitigating them and increasing the utilization of expensive network infrastructures, there is currently no available mechanism to monitor data transfers in these networks. In this paper, we present a scalable, end-to-end monitoring framework to gather and store key performance metrics for file transfers to shed light on the performance of transfers. The evaluation results show that the proposed framework can monitor up to 400 transfers per host and more than 40, 000 transfers in total while collecting performance statistics at one-second precision. We also introduce a heuristic method to automatically process the gathered performance metrics and identify the root causes of performance anomalies with an F-score of 87 - 98%.Comment: 11 pages, 7 figures, 6 table

10-14 YAŞ TENİSÇİLERDE 8 HAFTALIK CORE ANTRENMANLARININ ÇEVİKLİK, KUVVET, DENGE PERFORMANSINA VE TENİS BECERİLERİNE ETKİSİ

10-14 YAŞ TENİSÇİLERDE 8 HAFTALIK CORE ANTRENMANLARININ ÇEVİKLİK, KUVVET, DENGE PERFORMANSINA VE TENİS BECERİLERİNE ETKİSİ Arslan E. Aydın Adnan Menderes Üniversitesi Sağlık Bilimleri Enstitüsü Beden Eğitimi ve Spor Eğitimi Programı, Yüksek Lisans Tezi, Aydın, 2021. Amaç: Bu çalışma 10-14 yaş tenisçilerde 8 haftalık core antrenmanlarının kuvvet, çeviklik ve denge performansları ile tenis becerilerine etkisini belirlemeyi amaçlamaktadır. Gereç ve Yöntem: Çalışmaya EA Tenis Akademisi’nde tenis eğitimi gören 25 tenisçi gönüllü olarak katılmıştır. Tüm katılımcılara öncelikle dikey sıçrama, pro-agility çeviklik ve yıldız denge testleri ile ITN Tenis beceri testi uygulanmış, ardından 11 kişilik deney grubuna tenis antrenmanlarına ek olarak literatürde belirtilen doğrultuda 8 hafta süresince hafta 3 kez core antrenmanları yaptırılmıştır. Kontrol gurubunu oluşturan tenisçiler yalnızca tenis antrenmanlarına devam etmişlerdir. Core antrenmanlarının kuvvet, çeviklik ve denge performansı ile tenis becerilerine etkisinin incelenmesi için 8 hafta sonunda ön testlemelerde uygulanan testler tekrar tüm katılımcılara uygulanmıştır. Çalışmada alınan ön test-son test ölçümleri kullanılarak 8 haftalık core antrenmanlarının 10-14 yaş tenisçilerin kuvvet, reaktif çeviklik ve denge performansları ile tenis becerilerine etkisi belirlenmiştir. Bulgular: İstatistiksel analiz sonuçlarına göre core antrenmanlarının deney grubundaki tenisçilerin ITN numaraları, ITN puanları, çeviklik ve denge becerilerinde istatistiksel olarak anlamlı bir ilerleme görülmüştür. Ayrıca kontrol grubunda ITN numaraları, ITN puanlarında ve yıldız denge testinde sınırlı yönlerde istatistiksel olarak anlamlı bir farka rastlanmıştır. Buna karşılık dikey sıçrama ve yaylanarak sıçrama test skorlarında her iki grupta da istatistiksel olarak anlamlı farka rastlanmamıştır. Sonuç: Sonuç olarak core antrenmanlarının 10-14 yaş tenisçilerde çeviklik, denge ve tenis performansına olumlu yönde katkılarının olduğu sonucuna ulaşılmıştır. Antrenman programlarında tenis antrenmanlarına ek olarak uygulanacak core antrenmanlarının sporcuların gelişimine katkı sağlayacağı düşünülmektedir.KABUL VE ONAY SAYFASI i TEŞEKKÜR ii SİMGELER VE KISALTMALAR DİZİNİ vi ŞEKİLLER DİZİNİ vii RESİMLER DİZİNİ viii TABLOLAR DİZİNİ ix ÖZET x ABSTRACT xi 1. GİRİŞ 1 1.1. Problemin Tanımı ve Önemi 2 1.2. Araştırmanın Amacı 2 1.3. Araştırmanın Hipotezleri 3 1.4. Varsayımlar 4 1.5. Sınırlılıklar 4 2. GENEL BİLGİLER 5 2.1. Tenisin Temel Özellikleri Teknik Bileşenleri 6 2.1.1. Temel Tenis Teknikleri 6 2.1.1.1. Forehand Vuruşu 6 2.1.1.2. Backhand Vuruşu 7 2.1.1.3. Servis 8 2.1.1.4. Vole 9 2.2. Temel Vuruş Teknikleri ve Uluslararası Tenis Numarası (ITN) 9 2.3. Tenisin Fiziksel ve Fizyolojik Gereksinimleri 10 2.3.1. Çeviklik 12 2.3.1.1. Statik Denge 13 2.3.1.2. Dinamik Denge 13 2.3.2. Kuvvet 14 2.3.3. Sıçrama 15 2.3.3.1. Yatay (horizontal) Sıçrama 15 2.3.3.2. Dikey (vertikal) Sıçrama 15 2.3.3.3. Derinlik Sıçrama 16 2.4. Core Antrenmanı 16 2.4.1. Core Nedir? 16 2.4.2. Core Anatomisi ve Core Kasları 17 2.4.3. Core Antrenmanları 18 2.4.4. Core Stabilizasyon 19 2.4.5. Core Kuvveti 20 2.4.6. Core Antrenmanlarda Dikkat Edilmesi Gereken Hususlar 20 2.4.7. Core Antrenmanda Kullanılan Ekipmanlar 21 2.5. Core Antrenmanının Tenis Üzerindeki Etkileri 21 3. GEREÇ VE YÖNTEM 23 3.1. Çalışma Grubu 23 3.2. Yerleşim 24 3.3. Yöntem 24 3.3.1. Antropometrik Ölçümler 24 3.3.2. Performans Testleri 24 3.3.2.1. Statik Dikey Sıçrama (DS) 25 3.3.2.2. Yaylanarak Sıçrama (YS) 26 3.3.2.3. Pro-Agility Çeviklik Testi 26 3.3.2.4. Yıldız Denge Testi 27 3.3.3. Tenis Beceri Testleri 28 3.3.3.1. Yer Vuruşları Derinlik ve Güç Testi 28 3.3.3.2. Vole Derinliği ve Kuvveti 29 3.3.3.3. Temel Vuruş Doğruluğu 30 3.3.3.4. Servis Vuruş Derinliği ve Sürati 31 3.3.3.5. Çabukluk Testi 32 3.3.4. Sekiz Haftalık Core Antrenmanları 33 3.3.5. İstatistiksel Değerlendirme 35 4. BULGULAR 36 5. TARTIŞMA 41 6. SONUÇ VE ÖNERİLER 45 KAYNAKLAR 46 EKLER 56 Ek 1. Etik Kurul Onayı 56 Ek 2. Bilgilendirilmiş Gönüllü Olur Formu 57 Ek 3. Veli Bilgilendirilmiş Gönüllü Olur Formu 62 Ek 4. Kurum İzinleri 67 BİLİMSEL ETİK BEYANI 68 ÖZ GEÇMİŞ 69

I/O Burst Prediction for HPC Clusters using Darshan Logs

Understanding cluster-wide I/O patterns of large-scale HPC clusters is essential to minimize the occurrence and impact of I/O interference. Yet, most previous work in this area focused on monitoring and predicting task and node-level I/O burst events. This paper analyzes Darshan reports from three supercomputers to extract system-level read and write I/O rates in five minutes intervals. We observe significant (over 100x) fluctuations in read and write I/O rates in all three clusters. We then train machine learning models to estimate the occurrence of system-level I/O bursts 5 - 120 minutes ahead. Evaluation results show that we can predict I/O bursts with more than 90% accuracy (F-1 score) five minutes ahead and more than 87% accuracy two hours ahead. We also show that the ML models attain more than 70% accuracy when estimating the degree of the I/O burst. We believe that high-accuracy predictions of I/O bursts can be used in multiple ways, such as postponing delay-tolerant I/O operations (e.g., checkpointing), pausing nonessential applications (e.g., file system scrubbers), and devising I/O-aware job scheduling methods. To validate this claim, we simulated a burst-aware job scheduler that can postpone the start time of applications to avoid I/O bursts. We show that the burst-aware job scheduling can lead to an up to 5x decrease in application runtime.Comment: 10 pages, 11 figures, 2 table

Service-aware multi-resource allocation in software-defined next generation cellular networks

Şefik Şuayb Arslan (MEF Author)Network slicing is one of the major solutions needed to meet the requirements of next generation cellular networks, under one common network infrastructure, in supporting multiple vertical services provided by mobile network operators. Network slicing makes one shared physical network infrastructure appear as multiple logically isolated virtual networks dedicated to different service types where each Network Slice (NS) benefits from on-demand allocated resources. Typically, the available resources distributed among NSs are correlated and one needs to allocate them judiciously in order to guarantee the service, MNO, and overall system qualities. In this paper, we consider a joint resource allocation strategy that weights the significance of the resources per a given NS by leveraging the correlation structure of different quality-of-service (QoS) requirements of the services. After defining the joint resource allocation problem including the correlation structure, we propose three novel scheduling mechanisms that allocate available network resources to the generated NSs based on different type of services with different QoS requirements. Performance of the proposed schedulers are then investigated through Monte-Carlo simulations and compared with each other as well as against a traditional max-min fairness algorithm benchmark. The results reveal that our schedulers, which have different complexities, outperform the benchmark traditional method in terms of service-based and overall satisfaction ratios, while achieving different fairness index levels.WOS:000430793600019Scopus - Affiliation ID: 60105072Science Citation Index ExpandedQ1 - Q2ArticleUluslararası işbirliği ile yapılmayan - HAYIRMart2018YÖK - 2017-1

Ocena czynników ryzyka w odmianie wysokokomórkowej przerzutowego/ /nawrotowego raka brodawkowatego tarczycy

Introduction. Papillary thyroid carcinoma (PTC) is the most common malignant thyroid tumor. A great majority of the cases live a disease-free life with quite favorable prognosis. There are lots of variants of PTC and a few of them exhibit aggressive behaviour. Typical example is the tall cell variant (TCV). Patients experience a greater incidence of recurrence, nodal and extranodal metastases, tumor associated mortality than other variants of PTC. Studies related to TCV almost always compared it with its patient population of PTC according to risk factors and clinicopathologic features. The aim of this study is to evaluate the risk factors in metastatic/recurrent TCV. Materials and Methods. This is a retrospective cohort study of 1813 patients with differentiated thyroid carcinoma treated with radioiodine between 1992 and 2011. 56 of these patients are TCV. 34 of them developed metastasis/recurrence and 22 lived a disease-free life during the 23-year follow-up. We evaluated the risk factors in these metastatic and nonmetastatic subgroups. Results. We found tumor size, preablation thyroglobulin level, vascular invasion, preablation central and lateral cervical lymph node metastasis, preablation lung metastasis and stage independent risk factors. However age, preablation thyroglobulin level and stage appeared together as striking factors impacting metastasis in multivariate analysis. Conclusion. Higher ablation doses up to 250-300 mCi should be administered to TCV patients having advanced stage (III,IV), pretty high preablation thyroglobulin level (over 400 ng/ml) and older age (over 52 years) especially with large tumor size (over 3.5 cm) and initial cervical lymph node metastasis.Wstęp. Rak brodawkowaty tarczycy (papillary thyroid carcinoma, PTC) jest najczęstszym nowotworem złośliwym tego narządu. U przeważającej większości chorych możliwe jest całkowite wyleczenie, a rokowanie jest dobre. Występuje wiele odmian PTC, spośród których nieliczne są bardziej agresywne. Typowym przykładem takich nowotworów jest odmiana wysokokomórkowa (tall cell variant, TCV). Cechuje się ona częstszym występowaniem wznów, przerzutów do węzłów chłonnych i pozawęzłowych oraz większą śmiertelnością z powodu choroby nowotworowej niż inne odmiany PTC. Badania dotyczące TCV niemal zawsze mają na celu porównanie tej grupy chorych z populacją chorych na PTC w odniesieniu do czynników ryzyka oraz parametrów klinicznych i patomorfologicznych. Celem niniejszego badania jest ocena czynników ryzyka w przerzutowym/nawrotowym TCV. Materiał i metody. Było to retrospektywne badanie kohortowe obejmujące 1813 chorych ze zróżnicowanym rakiem tarczycy leczonych jodem promieniotwórczym w latach 1992–2011. U 56 osób z tej grupy rozpoznano TCV. U 34 z nich stwierdzono przerzut/nawrót, a w przypadku 22 chorych potwierdzono przeżycie wolne od choroby przez okres 4–23 lat. Autorzy ocenili czynniki ryzyka w podgrupach chorych z przerzutami i bez przerzutów. Wyniki. Stwierdzono, że niezależnymi czynnikami ryzyka są wielkość guza, stężenie tyreoglobuliny przed ablacją, unaczynienie guza, przerzuty to węzłów chłonnych szyjnych środkowych i tylnych oraz do płuc przed ablacją, a także stopień zaawansowania choroby. Jednak najważniejszymi czynnikami ryzyka przerzutów w analizie wieloczynnikowej okazały się wiek, stężenie tyreoglobuliny przed ablacją i stopień zaawansowania choroby nowotworowej. Wnioski. U chorych z TCV w zaawansowanym stadium (III, IV), z wysokimi stężeniami tyreoglobuliny (> 400 ng/ml) i w starszym wieku (> 52 lata), a zwłaszcza u osób z dużym rozmiarem guza (> 3,5 cm) i obecnymi przerzutami do węzłów chłonnych szyjnych, należy stosować wyższe dawki ablacyjne wynoszące do 250–300 mCi.