scholarly journals Designing Highly Loaded Systems

2020 ◽  
Vol 32 (6) ◽  
pp. 79-86
Author(s):  
Vasilii Andreevich Rudometkin
Keyword(s):  
System Architecture ◽  
Negative Impact ◽  
High Load ◽  
High Availability ◽  
Data Loss ◽  
Reading And Writing ◽  
System Components ◽  
To Receive ◽  
Highly Loaded

Nowadays, most of the services are moving online, which allows users to receive the service at any time. The high availability of the service leads to an increase in the number of users, which entails an increase in the load on the system. High load has a negative impact on system components, which can lead to malfunctions and data loss. To avoid this, the article discusses several design and monitoring approaches, the observance of which will help prevent system malfunctioning. The article describes the most popular way to distribute the area of responsibility of each service, in accordance with the DDD pattern, the use of which will allow you to separate the components of the system logically by use and physically when scaling the system. This approach will also be useful when scaling a team and allow developers to work independently on different system components without interfering with each other. The integration of new people into the project will also take the shortest possible time. When designing the system architecture, it is worth paying attention to the scheme of interaction between services. Using the CQRS pattern allows you to separate reading and writing into different components, which later allows the user to quickly receive a response from the system. Particular attention in the article is paid to monitoring the system, since with an increase in the size of the system, the time to search for errors in the system reaches a large amount of time, which can lead to a long unavailability of the system, which will entail the loss of clients. All the methods described in the article have been applied on many projects, for example, MTS POISK. Thanks to a properly designed system, it was possible to reduce the waiting time for a service response from two minutes to several seconds without losing the quality of the result, and a sophisticated system monitoring system allows you to monitor all processes within the system in real time and prevent accidents. As a result, at the beginning of the system design, special attention should be paid to the architecture, the issue of monitoring and testing the system. Subsequently, these temporary investments will reduce the risks of data loss and system unavailability.

Increasing the resiliency of highly loaded systems

2020 ◽  
pp. 118-123
Author(s):  
В.А. Рудометкин
Keyword(s):  
Fault Tolerance ◽  
High Load ◽  
High Availability ◽  
Distributed Transactions ◽  
Microservice Architecture ◽  
To Receive ◽  
Processor Cores ◽  
Highly Loaded

В настоящее время большинство сервисов переходят в онлайн, что позволяет пользователям получать услугу в любое время. Высокая доступность услуги приводит к росту количества пользователей, что влечет за собой повышение нагрузки на систему, поэтому необходимо уделить особое внимание отказоустойчивости системы перед началом ее разработки. Рассматриваются основные проблемы высоконагруженных систем, способ оптимизации приложения путем распараллеливания задач по ядрам процессора. В данной статье описывается необходимость перехода на микросервисную архитектуру, ее недостатки и способы их устранения. В процессе решения проблем масштабирования, затрагиваются проблемы распределенных транзакций и долгого ответа от сервера. Nowadays, most of the services are moving online, which allows users to receive the service at any time. The high availability of the service leads to an increase in the number of users, which entails an increase in the load on the system, therefore, it is necessary to pay special attention to the fault tolerance of the system before starting its development. The main problems of high-load systems, a way to optimize an application by parallelizing tasks across processor cores are considered. This article describes the need to migrate to a microservice architecture, its weaknesses, and how to fix them. In the process of solving scaling problems, the problems of distributed transactions and long response from the server are addressed.

scholarly journals Implementation and verification of high data availability on database

2019 ◽  
Vol 7 (5) ◽  
Author(s):  
Yen-Jen Chen ◽  
Han Tsai
Keyword(s):  
System Architecture ◽  
Management System ◽  
Database Management ◽  
Hard Disk ◽  
Data Access ◽  
High Availability ◽  
Database Management System ◽  
Test Method ◽  
Cache Memory ◽  
Data Loss

This study provides a low-cost and high-availability database management system architecture for general Small/Medium Enterprises (SMEs) to backup database data access. To prove that the proposed architecture can support the high availability of the database, and can effectively avoid data loss in memory caused by failovers, this study applies the main test method of powering off the virtual machine and verified three cases on two commonly used databases MySQL and PostgreSQL: Case 1 proves that this study combines the database native disaster recovery mechanism to effectively achieve high availability of the database. Case 2 proves that it effectively controls the WAL (Write Ahead Log) of the PostgreSQL database and Redo log mechanism of the MySQL database, so that data correctness is maintained during failovers. Case 3 proves that it can analyze and control the timing of the database in writing data in the cache memory to the hard disk. This study also designed a failover process to avoid data loss during failovers due to no enough time to write the data in the cache memory back to the hard disk; and finally to realize the high-availability of the database management system architecture in a practical way.   Keywords: Database, DBMS, High Availability, Failover, DRBD

State Healthcare and the Impact of Remittances on Turnout in Mexico

2016 ◽  
Vol 1 (1) ◽  
pp. 65-104
Author(s):  
Ana Isabel Lopez Garcia
Keyword(s):  
Voter Turnout ◽  
Regression Models ◽  
Negative Impact ◽  
Negative Relationship ◽  
Local Elections ◽  
Seguro Popular ◽  
Free Healthcare ◽  
The Impact ◽  
To Receive

In Mexico remittances have long been used to compensate for the lack of coverage and quality of state-provided healthcare. Since the mid-2000s, however, those without insurance have been entitled to receive free healthcare via the Seguro Popular programme. While popular, the delivery of this scheme is highly localised and therefore vulnerable to political manipulation. Using a series of regression models based on data at the municipality level, this paper analyses all local elections in Mexico between 2010 and 2012 and the presidential election of 2012 to confirm results of the previous literature which found a negative relationship between remittances and voter turnout. However, the analysis reveals that the negative impact of remittances on turnout becomes larger with additional increases in the coverage of Seguro Popular, though only in those municipalities where the PRI (the former hegemonic party) is electorally strong. The evidence thus confirms that the discretionary character of welfare provision modulates the effect of remittances on turnout in sending municipalities, but only where party-based authoritarianism prevails.

Lesson Study dan Implikasinya Terhadap Pembelajaran Berbasis Kurikulum Tingkat Satuan Pendidikan

2016 ◽  
Vol 1 ◽  
pp. 189-196
Author(s):  
Vian Harsution
Keyword(s):  
Learning Environment ◽  
Learning Process ◽  
Lesson Study ◽  
Learning Difficulties ◽  
Learning Needs ◽  
Democratic Leadership ◽  
Entrepreneurial Spirit ◽  
To Receive

Lesson study is a systematic, collaborative, and sustainable method of improving the quality of learning. Lesson study emphasizes the exploration of students’ learning needs; teacher openness towards learning difficulties encountered; the willingness of teachers to receive and provide advice and solutions to the difficulties encountered; and the consistency of the various parties to follow up the suggestions and solutions. Implementation of lesson study involving teachers, principals, and experts in the field of education. Kurikulum tingkat satuan pendidikan or abbreviated KTSP is operational curriculum formulated and implemented by each educational unit. KTSP has the characteristics, namely: giving broad autonomy to the educational unit, involving the community and parent participation, involving the democratic leadership of the principal, and require the support of a working team that is synergistic and transparent. KTSP based on the learning process, needs to be supported by a conducive learning environment and fun to be created by teachers.Teachers and principals in a professional, systematic and collaborative create an atmosphere that fosters independence, tenacity, entrepreneurial spirit, adaptive and proactive nature of the learning process. Thus, the learning needs of students who fulfilled optimally and professional ability of teacher who have increased on an ongoing basis, may usher in success – based learning KTSP. It means that the lesson study provides positive implications for the KTSP – based learning.

Green Beans Cultivation Using Mice Pets Control to Improve the Quality of Bintaro Fruit Extract

2018 ◽  
Vol 1 (1) ◽  
pp. 38
Author(s):  
Ajeng Embri Legawati ◽  
Nur Azizah ◽  
Achmad Ramadhan
Keyword(s):  
Natural Resources ◽  
Negative Impact ◽  
Green Beans ◽  
Fruit Extract ◽  
Bean Plants ◽  
Cultivation Technology ◽  
Environmental Balance ◽  
The Impact ◽  
Chemical Pesticides

Green beans cultivation technology using mice pets control has been implemented in the Gluranploso village, Benjeng Gresik. The implementation of the technology performed for 2.5 months from August to October 2017. The purpose of the implementation is aimed to reduce the dependence of farmers on the use of chemical pesticides so that the farmers are aware of the negative impact of chemical pesticides. Assessing the impact of the utilization of Bintaro fruit and fruit extracts to explore ways of making Bintaro as a natural biopesticide to overcome rat attack on green bean plants in the Gluranploso village. Pest control mice can reduce the rate of loss of the crops more effectively and efficiently. Finally, with the use of those natural resources as a biopesticide material can also maintain the environmental balance

CHRONOBIOLOGICAL AND PSYCHOEMOTIONAL STATUS IN WOMEN WITH CHRONIC RECURRENT BACTERIAL CYSTITIS AND CARBOHYDRATE METABOLISM DISORDER

2020 ◽  
pp. 56-59
Author(s):  
Мария Николаевна Химичева ◽  
Андрей Владимирович Кузьменко ◽  
Владимир Васильевич Кузьменко ◽  
Тимур Асланбекович Гяургиев
Keyword(s):  
Chronic Disease ◽  
Carbohydrate Metabolism ◽  
Negative Impact ◽  
High Risk Group ◽  
Chronic Complications ◽  
Course Of Disease ◽  
Metabolism Disorder ◽  
Common Group ◽  
Tract Infections

Инфекции мочевых путей - наиболее распространённая группа заболеваний в практике врача уролога. Один из представителей является хронический рецидивирующий бактериальный цистит. Данное заболевание встречается во всех возрастных категориях и затрагивает все сферы жизни пациентов. Симптомы, возникающие при обострении хронического бактериального цистита, оказывают негативное влияние на качество жизни, что может приводить к нарушению психоэмоционального состояния больных. Отдельную группу высокого риска в отношении ИНМП составляют пациенты с нарушением углеводного обмена, у которых риск развития различных инфекций выше, чем у людей без подобных нарушений. К факторам, повышающим риск развития ИНМП у больных с нарушением углеводного обмена, относят возраст, компенсацию и наличие хронических осложнений, в первую очередь нефропатии и цистопатии. Человеческий организм функционирует циклически в соответствии с определенными индивидуальными ритмами. Любое хроническое заболевание приводит к рассогласованию процессов, протекающих в различных системах организма, вызывая развитие десинхроноза. Наличие у человека более 1 хронического заболевания утяжеляет течение болезни и приводит к снижению восстановительных способностей организма и сокращению его адаптационного потенциала Urinary tract Infections are the most common group of diseases in the practice of a urologist. One of the representatives is chronic recurrent bacterial cystitis. This disease occurs in all age categories and affects all areas of life of patients. Symptoms that occur with the exacerbation of chronic bacterial cystitis have a negative impact on the quality of life, which can lead to a violation of the psychoemotional state of patients. A separate high-risk group for INMP is patients with impaired carbohydrate metabolism, who have a higher risk of developing various infections than people without such disorders. Factors that increase the risk of developing INMP in patients with impaired carbohydrate metabolism include age, compensation, and the presence of chronic complications, primarily nephropathy and cystopathy. The human body functions cyclically in accordance with certain individual rhythms. Any chronic disease leads to misalignment of the processes occurring in various body systems, causing the development of DS, the Presence of more than 1 chronic disease complicates the course of disease and leads to a decrease in regenerative abilities of the organism and reduce its adaptive capacity

Modern challenges of border areas development in the context of decentralization reform

2019 ◽  
pp. 79-89
Author(s):  
Khrystyna Prytula ◽  
Yaroslava Kalat ◽  
Iryna Kyryk
Keyword(s):  
Ethnic Minorities ◽  
Negative Impact ◽  
Local Development ◽  
Economic Security ◽  
Uneven Development ◽  
Scientific Article ◽  
Border Regions ◽  
Border Areas ◽  
Decentralization Reform

An integral part of the implementation of any reform is the emergence of the risks of its negative impact on one or another area of region development. The decentralization reform in Ukraine is not an exception. In its the context the most probable occurrence of negative phenomena is in the border regions, which could be prevented by first detecting them. In the scientific article, the authors focus on the analysis of a number of challenges for the development of border regions in the context of decentralization reform. Given the territorial remoteness of the central regions of the country and the capital, which today serve as areas of concentration of investment and economic activity, the border regions traditionally (this is typical for the border areas of the EU member states) lag behind the rest of the regions by the main socio-economic indicators of development. Among the main challenges facing the border regions of Ukraine today are the following: the provision of competitiveness in the context of European integration processes and reduction of the border barrier function; low level of economic security; the outflow of human capital and the issue of ethnic minorities. Based on an expert survey of representatives of the fifteen united territorial communities (UTCs), the possibility of such risks of decentralization in the border regions were defined as following: groundless use of local budget funds; emergence of significant imbalances between delegated new authority and available financial resources of the community; increasing uneven development of territories within the community; increasing uneven development of communities within the country; deterioration of the availability and quality of providing educational and medical services; deterioration of the quality of local government; reducing of the state influence on the management of local development processes; radicalization of political unions representing the interests of ethnic minorities in places of their compact residence; further economic decline of the territory of communities and so on.

The Microbial Quality of a Wetland Reclamation Facility Used to Produce an Effluent for Unrestricted non-Potable Reuse

1999 ◽  
Vol 40 (4-5) ◽  
pp. 369-374 ◽  
Author(s):  
R. S. Fujioka ◽  
A. J. Bonilla ◽  
G. K. Rijal
Keyword(s):  
Fecal Coliform ◽  
Heterotrophic Bacteria ◽  
Fecal Indicator ◽  
Potable Reuse ◽  
Wetland Reclamation ◽  
Treated Sewage ◽  
Influent Water ◽  
Human Viruses ◽  
To Receive

An auxiliary Wetland Reclamation Facility (WRF) was constructed to receive stabilization pond treated sewage and further treat it with water hyacinth ponds, chemical flocculation, filtration and ultraviolet light disinfection. This was the first facility in Hawaii which was approved to produce the highest quality reclaimed water using alternative treatment schemes. We assessed the effectiveness of the WRF by monitoring water samples after each of the WRF treatment schemes for five genetically different groups of sewage borne microorganisms (fecal coliform, enterococci, C. perfringens, FRNA phage, total heterotrophic bacteria). The concentrations of all fecal indicator microoganisms, especially FRNA phase were low in the influent water to the WRF indicating that extended pond treatment may be especially effective in removing human viruses from sewage. The WRF treatment scheme was calculated to be able to reduce >99.99% of fecal coliform and therefore was able to produce an effluent meeting the non-potable, unrestricted reuse standard of a geometric means of <1 fecal coliform/100 ml.

Prospective Randomized Trial Comparing Mitomycin, Cisplatin, and Protracted Venous-Infusion Fluorouracil (PVI 5-FU) With Epirubicin, Cisplatin, and PVI 5-FU in Advanced Esophagogastric Cancer

2002 ◽  
Vol 20 (8) ◽  
pp. 1996-2004 ◽  
Author(s):  
P. Ross ◽  
M. Nicolson ◽  
D. Cunningham ◽  
J. Valle ◽  
M. Seymour ◽  
...  
Keyword(s):  
Randomized Study ◽  
Squamous Carcinoma ◽  
Undifferentiated Carcinoma ◽  
Palmar Erythema ◽  
Esophagogastric Cancer ◽  
Equivalent Efficacy ◽  
Venous Infusion ◽  
Grade 3 ◽  
To Receive

PURPOSE: We report the results of a prospectively randomized study that compared the combination of epirubicin, cisplatin, and protracted venous-infusion fluorouracil (PVI 5-FU) (ECF) with the combination of mitomycin, cisplatin, and PVI 5-FU (MCF) in previously untreated patients with advanced esophagogastric cancer. PATIENTS AND METHODS: Five hundred eighty patients with adenocarcinoma, squamous carcinoma, or undifferentiated carcinoma were randomized to receive either ECF (epirubicin 50 mg/m2 every 3 weeks, cisplatin 60 mg/m2 every 3 weeks and PVI 5-FU 200 mg/m2/d) or MCF (mitomycin 7 mg/m2 every 6 weeks, cisplatin 60 mg/m2 every 3 weeks, and PVI 5-FU 300 mg/m2/d) and analyzed for survival, response, toxicity, and quality of life (QOL). RESULTS: The overall response rate was 42.4% (95% confidence interval [CI], 37% to 48%) with ECF and 44.1% (95% CI, 38% to 50%) with MCF (P = .692). Toxicity was tolerable, and there were only two toxic deaths. ECF resulted in more grade 3/4 neutropenia and grade 2 alopecia, but MCF caused more thrombocytopenia and plantar-palmar erythema. Median survival was 9.4 months with ECF and 8.7 months with MCF (P = .315); at 1 year, 40.2% (95% CI, 34% to 46%) of ECF and 32.7% (95% CI, 27% to 38%) of MCF patients were alive. Median failure-free survival was 7 months with both regimens. Global QOL scores were better with ECF at 3 and 6 months. CONCLUSION: This study confirms response, survival, and QOL benefits of ECF observed in a previous randomized study. The equivalent efficacy of MCF was demonstrated, but QOL was superior with ECF. ECF remains one of the reference treatments for advanced esophagogastric cancer.

Sign in / Sign up

Export Citation Format

Share Document