down down
نویسندگان
چکیده
Performance prediction of checkpointing systems in the presence of failures is a well-studied research area. This paper makes three small contributions to this research area. First, we show how to apply the concept of availability from reliability theory as a useful metric for checkpointing systems. Second, we study the average availability of uniprocessor checkpointing systems, using the libckpt checkpointer as a model. This is a slight deviation from previous checkpointing models. We employ Bernoulli trials to derive an expression for the availability of such a checkpointing system, and then use this expression to calculate the checkpoint interval which maximizes availability. Third, we present another derivation of the availability based on a direct calculation of average segment uptime. For the exponential failure distribution function, these two derivations are equivalent. The latter derivation allows for a simple way to numerically approximate availability for other failure distribution functions. We conclude with examples of applying these results.
منابع مشابه
Stigma in Iranian Down Syndrome
Objectives: Stigma is a negative value. Many behaviors are to ward Stigmatized people. Down syndrome is one of conditions with Stigma. The aim of this study is to determine the sources of labeling in iranian Down syndrome. Methods: The View of 105 Down syndrome families concerning stigma were conducted. All of Down syndrome was under 50 years. Results: A fair proportion of Down syndrome f...
متن کاملبررسی میزان شیوع و عوامل مرتبط با زمین‌خوردن در سالمندان بالای 55 سال شهر شیراز
Objectives: Falling down is one of the most common problems that involve old people. It may affect the physical, emotional and social aspects of individual’s health and may cause economical and social problems for individuals and society. Methods & Materials: In a cross sectional study, 750 old people with ages of 55 or more, living in the city of Shiraz (409 female, 341 male, mean age...
متن کاملDetermination of the sensitivity and secificity of hypertrophy of hyponychium as a new diagnodtic sing in down syndrome
down syndrome is the most common known chromosomal disorder in man.this syndrome has many sings and symptoms which are variable in frequency.taking all the signs and symproms in to consideration,diagnosis of down syndrome is not a difficult task-however in the past it was difficult to diagnose this syndrome based on a single clinical sign,until hypertrophy of hyponichium was first introduced b...
متن کاملA Comparison of the Role of Family Functioning in Self-Worth and Happiness of Slow-Paced Individuals with Down Syndrome in Tehran and Baku
This study sought to compare the role of family functioning in self-worth and happiness of slow-paced individuals with Down syndrome in Tehran and Baku. The present research had a causal-comparative (ex post facto) design. The research population was comprised of adults with Down syndrome some of whom had the Alzheimer’s disease. Purposive sampling method was utilized and 40 adults with Down sy...
متن کاملمقایسه دو روش تحریک تخمک گذاری در مبتلایان به تخمدان پلی کیستیک مقاوم به کلومیفن درسیکل IUI با استفاده از گنادوتروپینLow-dose step-up و Step-down
Introduction: Polycystic ovary syndrome(PCOS) is one of the most common cause of infertility in women. clomiphene is the first line of treatment. however 20% of patients are resistant to clomiphene. because of follicular hypersensitivity to gonadotropins in pcod, multiple follicular growth and development occurs which is cause of OHSS and multiple pregnancy. Our aim of this random and clinical ...
متن کاملStudies Into the Omission of Take-Down Tension System in Circular Kniting Machanes (TECHNICAL NOTE)
This paper reports on an attempt to modify a circular knitting machine such that it would operate without the need for a customary tension system where a kinitting machine can operate without an asymmetric take-down system preliminary results appear promising and warrant further development.
متن کامل