Is Software Replication Really Faster in VS .NET

Creating QR Code ISO/IEC18004 in VS .NET Is Software Replication Really Faster
Is Software Replication Really Faster
Reading QR In .NET Framework
Using Barcode Control SDK for Visual Studio .NET Control to generate, create, read, scan barcode image in Visual Studio .NET applications.
In our experience, and counterintuitively, software-based replication is actually faster than hardware-based replication. The following are some of the reasons why:
Encode QR In .NET
Using Barcode maker for Visual Studio .NET Control to generate, create QR Code image in Visual Studio .NET applications.
Software replication solutions generally replicate smaller blocks of data than hardware-based solutions. Less data means that the transactions finish faster, and with less network traffic being generated. Smaller
QR Code Reader In .NET
Using Barcode reader for VS .NET Control to read, scan read, scan image in .NET framework applications.
18
Bar Code Maker In VS .NET
Using Barcode creator for Visual Studio .NET Control to generate, create barcode image in Visual Studio .NET applications.
chunks also mean that less unchanged data is replicated. A small local write can generate a much larger replicated write via hardware-based replication, which usually replicates data in the same-sized chunks each time. The same local write on most software-based replication products will send less data while replicating.
Decoding Barcode In .NET
Using Barcode scanner for Visual Studio .NET Control to read, scan read, scan image in Visual Studio .NET applications.
Hardware-based replication adds its overhead when it performs the write; that s when it begins the process of spawning off the replicated copy of the data. The moment of the actual disk write is the slowest part of the transaction. By spawning the write at that point during the process, the slowest part of the transaction is made even slower. Software-based replication is done much earlier in the process so that more of the writes wind up being done in parallel, making better use of resources. While it s certainly true that hardware-based replication s work is done on an independent CPU located inside the disk array, it can still have a significant effect on the computer system s CPU. So that it does not get swamped by incoming replication requests, some hardware solutions will put the CPU into an uninterruptible disk-wait state while the transaction is sent across the network and the confirmation is making the return trip. During a disk-wait, no other activity can be performed on the host CPU. On a busy system with a lot of data being replicated, this will seriously slow down the host as its CPU essentially stops working for the duration of the replication. Some hardware-replication solutions do not use TCP/IP as their native network. Unless your enterprise uses one of these other networks (such as ESCON), it may be necessary to slow down the delivery of each data packet across the network by encapsulating it inside a TCP/IP packet and then unencapsulating it on the other end. The encapsulation also serves to make the packet larger, further slowing down the replication process.
QR Code JIS X 0510 Printer In C#
Using Barcode generation for .NET framework Control to generate, create QR Code image in .NET framework applications.
We certainly understand that product improvements are being made all the time and that what is true about performance as we write this material may or may not be true when you read it. Therefore, we once again urge our readers to carefully evaluate the performance of any replication solution that you may be considering, and that you run relevant benchmarks to determine which solution will balance the best data protection with the least impact on application and system performance.
Painting QR-Code In VS .NET
Using Barcode encoder for ASP.NET Control to generate, create QR-Code image in ASP.NET applications.
Initiator-Based Type 3: Filesystem-Based Replication
QR Code Creation In VB.NET
Using Barcode encoder for VS .NET Control to generate, create Denso QR Bar Code image in .NET applications.
When you boil it down to its base components, filesystem-based replication is much like tape backup: a point-in-time copy of the files in a filesystem.
Creating Barcode In .NET Framework
Using Barcode creation for .NET Control to generate, create barcode image in .NET framework applications.
Data Replication
ECC200 Generator In VS .NET
Using Barcode drawer for .NET Control to generate, create DataMatrix image in VS .NET applications.
Hardware- and software-based replication, tape backups, and database products include fancy vendor-based tools, while filesystem-based replication tools are generally utilities that are included as part of the operating system. It is rare, though not unheard of, for filesystem-based replication to be used as a solution for DR. By its nature, filesystem-based replication is very similar to the periodic style of replication we discussed in the previous section: From time to time, the contents of a filesystem (or just the changes since last time) are collected and sent to the destination site. Filesystem replication is best used, then, to make a copy of a filesystem whose contents don t change very often, or perhaps to make a one-time copy. If contents change regularly, it is best to consider another method, such as hardware- or software-based replication. One excellent use of filesystem replication occurs when you have enough developers to outstrip the capacity of a single server, and the users are demanding multiple servers worth of development tools, library files, and manual pages. Multiple servers provide a basic level of redundancy against the failure of any one server and can remove performance bottlenecks by distributing the client load over several servers. Replicated read-only file servers can also be dropped in behind web servers, providing load balancing across multiple sources for the same content with the same measure of availability and performance. To be fair, though, this technique of replicating among colocated servers is falling into disuse as SANs are able to fill that niche without requiring separate copies of the data on each server. SANs can be configured to protect the data against most types of outages; for more on SANs, see 8, SAN, NAS, and Virtualization. Like mirroring, filesystem-based replication is not a substitute for backups, because replication only preserves the current state of the filesystem. If you need to restore your boss s email file from last Thursday, not even Siegfried and Roy2 could make it appear from a current remote copy. You need a multiple-level backup strategy. (As we discussed in 6, Backups and Restores, remember, backups are always your last line of defense against total and irrevocable data loss.) Replication is also not a snapshot mechanism, as we introduced in 7. Snapshots may give you a copy-on-write filesystem, which allows you to go backward in time and look at the filesystem before any particular change was made to it. Snapshots are useful for recovering damaged or missing files, because they track changes to files. However, those changes are usually only tracked on one filesystem, making it just as susceptible to single-site failures as a normal, non snapshot-based system.
Barcode Creator In .NET Framework
Using Barcode drawer for .NET Control to generate, create bar code image in VS .NET applications.
UPC Shipping Container Symbol ITF-14 Generation In Visual Studio .NET
Using Barcode creator for .NET Control to generate, create UPC Case Code image in .NET applications.
Data Matrix Recognizer In .NET
Using Barcode recognizer for .NET framework Control to read, scan read, scan image in .NET applications.
Encode Code 39 In Java
Using Barcode creation for Java Control to generate, create Code-39 image in Java applications.
Decode Code 128 In Visual Studio .NET
Using Barcode scanner for .NET framework Control to read, scan read, scan image in .NET applications.
Generate Code128 In C#.NET
Using Barcode encoder for VS .NET Control to generate, create Code-128 image in Visual Studio .NET applications.