Recovery from failures due to Mandelbugs in IT systems

Several studies have been carried out on software bugs analysis and classification for life and mission critical systems, which include reproducible bugs called Bohrbugs, and hard to reproduce bugs called Mandelbugs. Although software reliability in IT systems has been studied for years, there are only a few formal analytic models for recovery from Mandelbugs. This paper discusses in detail several real cases of Mandelbugs and presents a simple flowchart which describes the recovery processes implemented in IT systems for a large variety of Mandelbugs. The flowchart is based on more than 10 IT systems that are running in production. The paper then presents a closed-form expression of the mean time to recovery from these bugs. Measures of interest including mean time to recovery and system unavailability are computed. A numerical and parametric sensitivity analysis of the model parameters are carried out. This analysis allows the designer to find out important parameter(s) for the recovery from failures due to Mandelbugs

THE ROLE OF HERBAL IMMUNOMODULATORS AS ADJUVANT THERAPY FOR ASYMPTOMATIC AND MILDLY SYMPTOMATIC COVID-19: AN EXPLORATORY CLINICAL STUDY

Objectives: The objective of the study is to evaluate herbal immunomodulators (Septilin and Bresol) as a possible adjuvant therapy for the treatment of asymptomatic and mildly symptomatic COVID-19. Methods: Randomized, open-label, comparative clinical study. Subjects were randomized to either arm I [Septilin and Bresol+standard of care (SOC)] or arm II (SOC). This study was registered on CTRI (CTRI/2020/06/025801). Results: Subjects in arm I showed a greater reduction in levels of interleukin-6 tumor necrosis factor-α following treatment than in arm II. Subjects in arm I showed a greater increase in levels of interferon (IFN)-β and IFN-λ than those in arm II. There was a greater reduction in D-dimer in arm I than in arm II subjects (64.28% vs. 35.59%) and all arm I subjects had D-dimer values in the normal range compared to 70% of arm II subjects. There were statistically significant reduction in lactate dehydrogenase and neutrophil-to-lymphocyte ratio in arm I (p<0.016 and p<0.013, respectively). Clinical assessments during the post-illness convalescence period showed significant improvements in fatigue assessment scores and quality of life. Conclusion: This herbal combination as an adjuvant to SOC may provide additional long-term benefits in COVID-19 infection by reducing inflammation. This treatment may offer a good addendum for the management of post-COVID-19 illness

Recovery from Software Failures Caused by Mandelbugs

Software failures are still a major concern in mission- and enterprise-critical contexts, despite significant efforts spent in software testing. In fact, while software testing is effective against easily-reproducible bugs (Bohrbugs), it is considerably less suitable for dealing with bugs that lead to hard-to-reproduce failures (Mandelbugs). On the positive side, the elusive nature of Mandelbugs provides opportunities for failure recovery, which are investigated in this paper. Based on real cases of Mandelbugs in eleven Information Technology (IT) systems running in production, the paper proposes a model that describes the recovery processes in IT systems. It then presents closed-form expressions, and a numerical analysis, of the mean time to recovery, and the software (un)availability. This analysis allows the designer to compare recovery strategies, as well as to determine the parameters having a high influence on the efficacy of recovery from failures caused by Mandelbugs

Recovery from Software Failures Caused by Mandelbugs

Software failures are still a major concern in mission- and enterprise-critical contexts, despite significant efforts spent in software testing. In fact, while software testing is effective against easily-reproducible bugs (Bohrbugs), it is considerably less suitable for dealing with bugs that lead to hard-to-reproduce failures (Mandelbugs). On the positive side, the elusive nature of Mandelbugs provides opportunities for failure recovery, which are investigated in this paper. Based on real cases of Mandelbugs in eleven Information Technology (IT) systems running in production, the paper proposes a model that describes the recovery processes in IT systems. It then presents closed-form expressions, and a numerical analysis, of the mean time to recovery, and the software (un)availability. This analysis allows the designer to compare recovery strategies, as well as to determine the parameters having a high influence on the efficacy of recovery from failures caused by Mandelbugs