LTRF: Enabling High-Capacity Register Files for GPUs via Hardware/Software Cooperative Register Prefetching

Graphics Processing Units (GPUs) employ large register files to accommodate all active threads and accelerate context switching. Unfortunately, register files are a scalability bottleneck for future GPUs due to long access latency, high power consumption, and large silicon area provisioning. Prior work proposes hierarchical register file, to reduce the register file power consumption by caching registers in a smaller register file cache. Unfortunately, this approach does not improve register access latency due to the low hit rate in the register file cache. In this paper, we propose the Latency-Tolerant Register File (LTRF) architecture to achieve low latency in a two-level hierarchical structure while keeping power consumption low. We observe that compile-time interval analysis enables us to divide GPU program execution into intervals with an accurate estimate of a warp’s aggregate register working-set within each interval. The key idea of LTRF is to prefetch the estimated register working-set from the main register file to the register file cache under software control, at the beginning of each interval, and overlap the prefetch latency with the execution of other warps. Our experimental results show that LTRF enables high-capacity yet long-latency main GPU register files, paving the way for various optimizations. As an example optimization, we implement the main register file with emerging high-density high-latency memory technologies, enabling 8× larger capacity and improving overall GPU performance by 31% while reducing register file power consumption by 46%

Successful Surgical Intervention in An Unusual Case of Aspergillus Endocarditis with Acute Myeloid Leukemia

Endocarditis due to Aspergillus infection is a rare complication in patients with hematological malignancies. Here, we present a case of aspergillus endocarditis in a patient with acute myeloid leukemia (AML) successfully treated with antifungal therapy and surgical treatment. The patient was a 51 years old male, a known case of AML who was admitted to our medical center for evacuating his valvular vegetations and repairing his atrial septal defect. He underwent an open heart surgery to relinquish his thromboses and also received an antifungal regimen. The patient tolerated the procedure well and eight months after his surgery, the patient remains asymptomatic. Successful treatment of this severe case of aspergillus endocarditis justifies a multidisciplinary method to be as a safe and effective approach to manage these patients

Association between angiotensin II type 1 receptor gene polymorphism and metabolic syndrome in a young female Iranian population

BACKGROUND AND AIMS The overall prevalence of obesity and metabolic syndrome (MetS) is increasing among children and adolescents and can predispose to type II diabetes mellitus and cardiovascular disease. There are reported associations between an angiotensin II type I receptor gene polymorphism (AT(1)R/A1166C) with hypertension, myocardial infarction, insulin resistance and cardiovascular disease risk. In the present study, we aimed to investigate whether the AT(1)R/A1166C polymorphism was associated with MetS among adolescent Iranian girls. METHODS A total of 350 adolescent girls aged 15-17 years from high schools and different educational zones of Mashhad city participated in this population-based, genetic association study. Of these individuals, 101 patients had MetS (defined by the NCEP-ATP III criteria); the remaining 249 age-matched girls were considered as the control group. All subjects were genotyped for the AT(1)R/A1166C polymorphism using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. RESULTS Frequencies of the AA, AC and CC genotypes were 164 (65.9%), 80 (32.1%) and 5 (2.0%) in the control group and 79 (78.2%), 20 (19.8%) and 2 (2.0%) in patients, which were not consistent with the Hardy-Weinberg equilibrium (p <0.05 and p <0.001, respectively). Frequency of the AT(1)R C allele was found to be significantly lower in patients compared with controls (p <0.05). CONCLUSIONS Our findings suggested that the 1166C allele of AT(1)R gene may be associated with a decreased risk of MetS in adolescent Iranian female