كاشف الأعطال يلعب دورا مركزياَ في هندسة النظم الموزعة , إضافة إلى ذلك فإن
العديد من التطبيقات لديها قيود زمنية معينة و تحتاج كواشف الأعطال التي تؤمن
ضمانات زمنية معينة .
كاشف الاعطال هو متنبئ يوفر معلومات عن فشل العمليات ,لتستفيد من هذه
المعلومات خوارزميات التسامح مع الاخطاء .
في هذا المقال سنقدم تطبيق لبناء كاشف الأعطال , هذا التطبيق يستخدم نموذج مشترك
مكون من النموذج النبضي و النموذج التفاعلي.
حيث تم بناء كاشف الأعطال بالنموذج النبضي و من ثم تمت إضافة نموذج تفاعلي
ليصبح كاشف الأعطال بالنموذج المشترك حيث نستخدم النموذج النبضي لتقصير زمن
الكشف في كاشف الأعطال , و عندما لا يتم استقبال النبضة من قبل العملية الكشافة
ضمن الزمن المتوقع , هنا نستخدم النموذج التفاعلي ليقوم بعملية تحقق إضافية من حالة
العملية المراقبة .
Failure detection plays a central role in the engineering of
distributed systems. Furthermore, many applications have timing
constraints and require failure detectors that provide quality of
service (QoS) with some quantitative timeliness guarantees.
Therefore, they need failure detectors that are fast and accurate.
Failure detectors are oracles that provide information about process
crashes , they are an important abstraction for fault tolerance in
distributed systems. Although current failure detectors theory
provides great generality and expressiveness, it also possess
significant challenges in developing a robust hierarchy of failure
detectors.
In this paper, we propose an implementation of failure detectors.
this implementation uses a dual model of heartbeat and interaction.
First, the heartbeat model is adopted to shorten the detection time.
if the detecting process does not receive the heartbeat message in
the expected time, the interaction model is then used to check the
process further.
References used
T. D. Chandra and S. Toueg, “Unreliable failure detectors for reliable distributed systems,” Journal of the ACM, vol. 43,no. 2, pp. 225-267, 1996
S. Bansal, S. Sharma, and I. Trivedi, “Adaptive staircase multiple failure detector for parallel and distributed image processing” in Proceedings of the 1st International Conference on Recent Advances in Information Technology,Dhanbad,India, 2012, pp. 91-94
W. Chen, S. Toueg, and M. K. Aguilera, “On the quality of service of failure detectors,” IEEE Transactions on Computers, vol. 51, no. 5, pp. 561-580, 2002
In this paper, we propose an implementation of hierarchical failure
detectors, which depends on dividing the processes into sub-groups
and elect one leader called the main process .
The main process then distributes the remaining processes into
g
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