DEV Community: preetham.sasi

Everything about RAM...

preetham.sasi — Tue, 21 Apr 2020 18:22:59 +0000

What's your RAM? will be the first question our friend will put on us when we buy a PC. Because all he knows😆 is "more the RAM, more the speed". But how this statement holds in the background. In this article, I will be explaining all you need to know about RAM.

1. What is RAM
2. How DRAM works?
3. Developments in DRAMs
3.1 SIMM V/S RIMM
4. SDRAM v/s DDR SDRAM
4.1 DDRx SDRAM
5. non ECC v/s ECC
6. RAM Hierarchy
7. Before you buy

This article is mainly concentrated on Dynamic RAM. I'm not touching RAMs in supercomputers and Static RAM

1. What is RAM?

When I want to open a paint.exe file, within no time it will load. But want will happen in the background?🤔 The program loads the necessary data from the hard drive(where the application is installed) to the RAM instead of loading the entire application. Then RAM will process the data to Processor(CPU).

2. How DRAM works?🧐

DRAM(Dynamic RAM) consists of the millions of memory cells which consist of transistors and capacitors, Capacitor is like a bucket which stores a bit(1 for read and 0 for write) at a time.

Unfortunately, In the actual scenario capacitors will leak some charge, If they aren't charged again then they will forget for what they meant and finally dies

So, Capacitors are charged by some voltage dynamically to again read the data bits

Hence the name evolved as Dynamic RAM and this whole cycle is called as Clock cycle.

3. Developments in DRAMs

Generally, DRAM is asynchronous with the clock in nature. So, To overcome this drawback later Synchronous Dynamic RAM(SDRAM) is introduced which will be perfectly in synchronous with the clock, After the introduction of SDRAM the transfer rate of the RAM can be explained easily with clock speed. For instance, let's take a present DDR4 SDRAM which has the speed of 3200 MHz that means the RAM operates 3.2 billion cycles per second.

Indeed, it is necessary to know about the Single inline memory module(SIMM) and Daul inline memory module(DIMM) before knowing anything about SDRAM.

3.1 SIMM V/S DIMM

a. SIMM
SIMMs are mostly used in the early 1980s to 1990s systems, the famous among them are Pentium series and IBM systems.
SIMM uses 32-bit(4-byte) bus path, which means it will transfer 32 bits at a time. let us consider there is a DRAM of speed 100 MHz then total transfer rate of data can be calculated like

so the DRAM of 100MHz will process 400 MB/s data to the processor(CPU).

But, The advancement in RAMs in terms of speed SIMMs are replaced with RIMMs which can provide a much more data transfer rate.

b. DIMM

DIMMs are mainly used in this generation DRAMs thanks to the usage of 64-bit bus path(8-byte path), which means it will transfer 64 bits at a time.
Let us suppose a present-day DDR4 SDRAM with 3200mhz speed, then transfer rate can be calculated as

Hence it will process around 25600 MB/s to the processors

Special type DIMM is used in laptops and portable PC's which is SO-DIMM(small outline DIMM)

4. SDRAM v/s DDR SDRAM

SDRAM sends data at a single rate only at a rising edge of the clock cycle. But later on, Double Data rate SDRAM(DDR SDRAM) is introduced which sends Double data(both at rising and falling edges)of the clock cycles.

4.1 DDRx SDRAM

To fasten the processing time of the application to the users, Processors are upgrading periodically. consequently, To support the high processing speed the same amount of powerful RAMs are needed. Thus the DDR class RAMs are constantly improved.

The main differences in DDR class RAMs are tabulated below

Actually DDR5 expected to launch in 2018 and 2019 but didn't happen😟. But, Lot of buzz going around that DDR5 will hit the market at the end of 2020.

5. Non ECC v/s ECC

The ordinary RAMs are generally non-ECC(Error-correcting code) while ECC RAMS are commonly used in servers.
Nowadays servers play a crucial role in different departments like health, public and private sectors, Thus the RAMs in these servers are maintained carefully intended to support 24*7. In case of any errors reported while data processing they can detect the errors and correct back.

ECC RAMs has 9 memory chips whereas non-ECC RAMs has 8 memory chips.

6. RAM Hierarchy

7. Before you buy

If you use PC for casual purposes like simple browsing, videos and music then 4GB DDR SDRAM will be abundant. In case of busy employees who needs to work with corporate tools like VMWare, Android studios, Adobe character animators then you can grab from 8GB DDR SDRAM. But if you are a serious gamer or a guy who uses 20 tabs of chrome on the spot you need to clutch 16GB DDR SDRAM. However, This much RAM will be more than enough but as they say "More is More"!!

And if you are planning to upgrade the RAM then make sure you have ticked these boxes

Checking the motherboard: As the different class of RAM has different fitting slots, checking the motherboard which RAM fits is recommended before buying.
If you are using 4GB DDR3 SDRAM for suppose, then the same amount of 4RAM DDR3 SDRAM ram is recommended because two RAMs which are operating at different clock speeds will result in slowing down the performance and ends up with heating💥 the motherboard as well.

Check out the illustration of present-day RAM

References:

https://en.wikipedia.org/wiki/Random-access_memory
https://en.wikipedia.org/wiki/SIMM
https://en.wikipedia.org/wiki/DIMM
https://www.youtube.com/watch?v=PVad0c2cljo

How SAP evolved and changed ERP?

preetham.sasi — Mon, 13 Apr 2020 08:44:17 +0000

The impact of SAP on today's business is humungous, The world is witnessing its ease of supporting to one's business in various departments. Let's see the cool stats😮 about SAP.

SAP is implemented in >4,00,000 companies and in >180 countries
In 2019 SAP turnover has recorded a staggering figure of 27.55 billion euros
Currently SAP supports 25 modules
SAP customers include:
92% of the Forbes Global 2000 companies

98% of the 100 most valued brands

97% of the greenest companies(Newsweek)
SAP customers distribute 78% and 82% of the world’s food and medical devices respectively

But this is not possible in overnight, The vision🔭 of SAP is sparked among a group of 5 friends before 48 years from now (2020).

1. History of SAP🔬

Dietmar Hopp, Hans-Werner Hector, Hasso Plattner, Klaus Tschira, and Claus Wellenreuther are former employees of IBM they noticed that all the companies are using similar business applications with minute varied requirements. So, They proposed to create standard business applications to eliminate reworks, errors-prone incidents, cost factor and to improve effectiveness. However, IBM didn't buy the idea and consequently, In 1972 they founded a company Systemanalyse und Programmentwicklung (System Analysis and Program Development) and later renamed it to Systeme, Anwendungen und Produkte in der Datenverarbeitung (Systems, Applications and Products in Data Processing) which is shortly called as SAP.

2. Evolution of SAP🧬

The first client for SAP is a German chemical company where SAP provides mainframes programs for payrolls and accounting programs. In 1972 SAP launched its first commercial system SAP R/1 which is a single-tier system and in 1979 SAP updated its business by launching SAP R/2 which is a two-tier system, R/2 was a great hit and bought fame for the company.

2.1 SAP R/3 Client-Server architecture

Adding boost to the SAP R/2, In 1992 SAP introduced SAP R/3 which is a Client-server architecture

Here, SAP maintained separate hardware for 3 individual systems.

They categorized the business into 3 layers

a. Presentation layer:
Presentation layer is typically a client system eg: SAP GUI, where the data is displayed in a user-friendly fashion.

b. Application layer:
Application layer mediates the data flow between the presentation layer and Database layer. It performs Read/Write operations with Database layer and presents the results to the presentation layer

c. Database layer:
Database layer stores the data in the form of tables and supports R/W operations to application layer

On a success note, Client-Server architecture bought a lot of success and made many business companies to look at SAP.

The same R/3 architecture was also implemented by various systems namely Oracle, MySQL, Mango DB, Micrsoftsqlserver etc.

SAP R/3 classified their business modules into 2 types

Technical Modules: All the technical and coding related stuff will be developed by SAP ABAP and SAP BASIS.

Functional modules: All the functionalities in real-time business are carried out by 11 main modules.

To have a glimpse😉 of SAP functional modules visit here

2.1.1 SAP R/3 4.6c and 4.7c

After the stable version of SAP R/3, SAP R/3 4.6c was the next version in R/3 class which includes Business plugins, Infructure addons.

Following 4.6c version, In the early 1990s due to the business movement to web application servers, SAP introduced one more version for R/3 class which is SAP R/3 4.7c and renamed the Basis module to Application web servers announcing that their latest support to application servers. This support is released via extension packs📦 instead of releasing a new next-generation ERP systems.

2.2 MySAP ERP 2003 and SAP NetWeaver 2003

In 2003, SAP introduced MySAP ERP Edition which is a huge Business suite and its a combination of SAP R/3 Enterprise, SAP NetWeaver along with some additional components related to the business.

At the same time, SAP SE implemented J2EE engine thanks for its ability to develop web applications and platform-independence. Due to this availability of Java programming SAP-integrated many integration components like SAP CRM, SAP Enterprise Portal and SAP Exchange Infrastructure, and SAP grouped components like XI, BW, EP and KP and named it as SAP NetWeaver.

2.3 MySAP ERP 2004 and SAP Netweaver 2004

In 2004, SAP introduced Enterprise Web Service. Stating briefly, A lot of web services should be run for a single process. For instance, Creation of a PO(placing an order to purchase an item) requires a web service for fetching item details and other web services for vendor details similarly a lot of services should be run to post PO. Hence, SAP adopted Enterprise Services Achitecture(ECA) to SAP R/3. As the SAP R/3 got a new component to its core they changed the name to ERP central component(ECC). Moreover, Enterprise Services Architecture changed to Enterprise Service-oriented Architecture(ESoA).

2.4 SAP ERP 2006 and SAP Netweaver 7.0

In 2005, MySAP ERP 2005 edition is introduced later changed to SAP ERP 6.0 (in 2006). SAP realized that even after grouping the individual components into NetWeaver it's not the way how the customers are using it up. Hence SAP Netweaver 2007 introduced Usage types for individual components. For instance, Before introducing usage types if we want to install XI lot of additional components should be installed but after, the XI usage type will spontaneously install every component.

After SAP ERP 6.0 we can say that SAP found a standard ERP model since then there are no much changes to the ERP model unless they provided constant extension packs to business. The most recent extension pack for SAP ERP 6.0 is "EHP08"(in 2016). Soon after that, it's monster time😈 SAP S/4 HANA

At the end of 2020 nearly 50% of global sap customers are planning🤔 to migrate from ERP to SAP S/4 HANA

2.5 SAP S/4 HANA

Here is the big fish, SAP SE after years of working experience with their customers. Finally wants to boost up their computing time⏳, portability, simplified UI and dream of using their database(HANA) came up with S/4 HANA where S is a Simplified data model, 4 signifies the fourth generation (after R/2, R/3 and ERP) and HANA meant to be High-performance analytical appliance.

2.5.1 Overview

SAP HANA is an SAP application which uses Inbuilt memory(RAM) to compute a lot of real-time data with less than a second.

Instead of performing R/W operations from hard disk which consumes a lot of computing time (usually happens in legacy systems), HANA performs R/W operations in RAM itself completing the tasks (OLAP & OLTP) under a second.

It's a known fact, that data volumes💽 are rocketing throughout the years and migration to the cloud database is the best solution which is implemented by SAP.
It uses a structural database where the data is stored in rows and columns of the tables. However, the column data is shirked to a large extent thanks to the developed compression techniques to fetch data faster than the row data.

Now, SAP enhancing it's ECC core to support🤝 HANA, let me illustrate some of HANA's cool features

Supply chain and retail optimization
Forecasting and profitability reporting
Database Services
Analytics and Data Processing
Application Development and Deployment
Data Access, Integration and Quality
Administration and IT Operations
Security and Multi-Engine

Although, Evolution of SAP underwent many versions it is the customer👔 satisfaction which bought SAP as a leading ERP systems provider.

References:

https://medium.com/@sapnwnewbie/evolution-of-sap-erp-architecture-in-11-steps-c060150a150c
https://www.sap.com/india/products/hana/features.html
https://www.saponlinetutorials.com/about-sap-modules-sap-modules-list-overview/
https://www.sap.com/documents/2017/04/4666ecdd-b67c-0010-82c7-eda71af511fa.html

What is fire?🔥

preetham.sasi — Sat, 04 Apr 2020 14:40:38 +0000

Introduction

It was Paleolithic period where the fire was first discovered thanks to early humans and stones(Spark from stones turned into the fire). However, throughout the era's applications of fire is rocketing in various areas from domestic needs to rocket sciences. Additionally, we can't deny the fact that most of the world disasters are also caused by fire accidents. So, This post describes the fundamental theory of fire.

What is Fire

Fire is an exothermic reaction where something like Wood, gasoline is shined with something like matches, steady light or friction in the presences of atmospheric air, generally known as combustion. The fire thus emits subsequent energies like light, heat and smoke(volatile gases).

Characteristics of fire

characteristics will be varied based upon the nature of materials, for instance, the heat factor in the wood or willow will be slightly less than dry grass. Not only the Heat factor but also the colour of flame will be varied between materials.

Fire is fast and furious😎
Fire has a serious pace of 6 MPH in the forest and 14 MPH in grasslands, once they caught up the situation will be furious.

Different levels of temperatures

Starting from the combustion point to peak point of the flame temperature is not the same it will be varied throughout. Starting at the Combustion point or Blue Zone the temperature recorded at ~800°, Moving to the Non-luminous zone and dark zone recorded at ~600° and ~1000° respectively, Finally going top luminous zone and luminous veil or peak flame point are noticed to be having ~1200° and ~1400° independently.

if you are a good observer the different zones of temperatures in the flame are having different colours 🧐. Guess what 🤔, due to the continuous chain reactions and strong bonding🤝 with atmospheric oxygen and wood's hydrocarbons the flame keeps on burning. So, the blue or green flame is due to the copper reaction while flickering red colour is because of strontium finally sodium gives the orange colour to the flame.

Types of Fires

Fires are classified based upon there nature of materials into different classes. let me elaborate one by one. Class A fires are grouped based on general usable things in daily life like wood, paper, clothes and plastic and can be easily dealt with water or wet clothes. Coming to Class B fires are something related to gases and lubricates. while the fires which are involved with electric appliances are classified as Class C. Class D fires are rear and formed when metal ignites.
Class E and Class F are generally related to household fires caused by vegetable oils.

Diasters😢

Although we are having a hell lot of uses with fires but there are an equal number of cases where the world witnessed numerous disasters. The disasters can be listed from leakage of LPG in the kitchens to the latest Australian bushfires. Amongst the noted fire accidents, Australian and Amazon bushfires are the nightmares for the nature to recover. consequently, an abundant species of flora🌴 and fauna🦘 whipped and burnt down to ashes.

References

https://science.howstuffworks.com/environmental/earth/geophysics/fire1.htm
https://www.insider.com/types-of-fires-and-how-to-put-them-out-2018-12

DEV Community: preetham.sasi

Everything about RAM...

Contents

1. What is RAM?

2. How DRAM works?🧐

3. Developments in DRAMs

3.1 SIMM V/S DIMM

4. SDRAM v/s DDR SDRAM

4.1 DDRx SDRAM

5. Non ECC v/s ECC

6. RAM Hierarchy

7. Before you buy

References:

How SAP evolved and changed ERP?

1. History of SAP🔬

2. Evolution of SAP🧬

2.1 SAP R/3 Client-Server architecture

2.1.1 SAP R/3 4.6c and 4.7c

2.2 MySAP ERP 2003 and SAP NetWeaver 2003

2.3 MySAP ERP 2004 and SAP Netweaver 2004

2.4 SAP ERP 2006 and SAP Netweaver 7.0

2.5 SAP S/4 HANA

2.5.1 Overview

What is fire?🔥

Introduction

What is Fire

Characteristics of fire

Different levels of temperatures

Types of Fires

Diasters😢