Big buffers. Download the clipboard manager and keep a complete history of copied data

A rare and happy combination of a thin waist and large breasts went to Salma Hayek! The actress, who has never had plastic surgery, emphasizes her dignity in every possible way - she loves tight-fitting dresses and things with a deep neckline. Of course!

Kate Upton

Model Kate Upton has repeatedly said that she would prefer to have smaller breasts, despite the fact that many girls dream of such a magnificent bust as hers. “I just dream of small breasts every day! I dream of wearing T-shirts thin spaghetti straps And don't wear a bra underneath. Life is much easier with breasts of the first size, ”Kate said in an interview.

Kelly Brook

Kelly Brook is the owner of a proud sixth breast size! And all natural, of course. True, the British model herself, like her colleague Kate Upton, is not at all happy about this. According to Kelly, because of her large breasts, she cannot wear dresses that she likes - a shame!

Scarlett Johansson

Scarlett Johansson has naturally prominent breasts, but there are rumors that the actress even reduced them! True, Scarlett herself never gave any comments about plastic surgery - fans can only guess whether this is true or not.

Christina Hendricks

But actress Christina Hendricks is very proud of her magnificent forms: it seems that there is no dress in Christina's wardrobe that would not emphasize her magnificent breasts.

Amber Rose

The curvy girl Amber Rose has everything of her own: both breasts and buttocks. To say that Amber is simply proud of her virtues is to say nothing! In any case, we rarely see a model in clothes: Amber prefers to be naked even in public.

Anna Semenovich

The controversy about the very magnificent bust of Anna Semenovich did not subside for quite a long time: natural or not? We, of course, take Anna's word for it - only nature can bestow such luxurious breasts.

Sofia Vergara

The sultry beauty Sofia Vergara is the owner of not only a beautiful figure, but also a magnificent chest. Sophia herself speaks of her bust with irony, in an interview with one of the glossy publications she said: “My bitches are just huge. Buying a bra has always been scary. When I moved to Los Angeles, the first thing I did was look for places like Frederick's that make stripper bras. There is nothing good in big breasts: when I lie down, they reach to the chin!

I wrote a json library that uses flex and bison to parse serialized-json (i.e. strings) and deserialize them to json objects. This works great for small strings.

However, it fails with very large strings (I've tried almost 3 GB strings) with this error:

‘fatal flex scanner internal error--end of buffer missed’

I want to know what is the maximum buffer size I can pass to this function:

//js: serialized json stored in std::string yy_scan_bytes(js.data(), js.size());

and how to make flex/bison work with large buffers?

Solution

It looks to me like you're using an old version of the flex framework (and therefore flex) where the string lengths had to match int s. The error message you're seeing is probably the result of int overflowing to a negative value.

I believe if you upgrade to version 2.5.37 or newer, you'll find that most int s have become size_t and you shouldn't have a problem calling yy_scan_bytes with an input buffer larger than 2 gigabytes. (The prototype of this function now takes size_t rather than int , for example.)

However, I find it hard to believe that this good idea. For starters, yy_scan_bytes copies the entire line, because the lexical scanner wants a string that it is allowed to modify, and because it wants to make sure the string has two NUL bytes at the end. Making this copy will uselessly take up a lot of memory, and if you're going to copy the buffer anyway, you can copy it in manageable chunks (say 64kb or even 1mb). This can only be problematic if you have single tokens that are significantly larger than the chunk size, because flex is definitely not optimized for large single tokens. But for all normal use cases, this will probably work much better.

Flex doesn't provide an interface for chunking the huge input buffer, but you can do it very easily by overriding the YY_INPUT macro. (If you do this, you will probably end up using yyin as a pointer to your own buffer structure, which is not theoretically portable. However, it will work on any Posix architecture where all object pointers have the same representation.)

Of course, you usually don't want to wait until 3 GB of data has accumulated in memory to start analyzing it. You can analyze step by step as you read the data. (You may still need to override YY_INPUT depending on how you're reading the data.)

Choosing a hard drive for a PC is a very responsible task. After all, it is the main repository of both official and your personal information. In this article, we will talk about the key characteristics of the HDD, which you should pay attention to when buying a magnetic drive.

Introduction

When buying a computer, many users often focus on the characteristics of its components such as monitor, processor, video card. And such an integral component of any PC as a hard drive (in computer slang - a hard drive), buyers often purchase, guided only by its volume, practically neglecting other important parameters. Nevertheless, it should be remembered that a competent approach to choosing a hard drive is one of the guarantees of comfort during further work at the computer, as well as financial savings, in which we are so often constrained.

The hard disk drive or hard disk drive (HDD) is the main data storage device in most modern computers, which stores not only the information the user needs, including movies, games, photos, music, but also the operating system, as well as everything installed programs. Therefore, in fact, the choice of a hard drive for a computer should be treated with due attention. Remember that if any element of the PC fails, it can be replaced. The only negative point in this situation is the additional financial costs for repairs or the purchase of a new part. But a hard drive failure, in addition to unforeseen costs, can lead to the loss of all your information, as well as the need to reinstall the operating system and all required programs. The main purpose of this article is to help novice PC users in choosing a hard drive model that would best meet the requirements of specific "users" for a computer.

First of all, you should clearly decide in which computer device the hard drive will be installed and for what purposes this device is planned to be used. Based on the most common tasks, we can conditionally divide them into several groups:

• A mobile computer for general tasks (working with documents, "surfing" the expanses of the World Wide Web, data processing and working with programs).
• Powerful mobile computer for gaming and resource-intensive tasks.
• Desktop computer for office tasks;
• A productive desktop computer (working with multimedia, games, audio, video and image processing);
• Multimedia player and data storage.
• To assemble an external (portable) drive.

In accordance with one of the listed options for operating a computer, you can begin to select according to the characteristics suitable model hard drive.

Form Factor

Form factor is the physical size of a hard drive. Today, most drives for home computers are 2.5 or 3.5 inches wide. The first, which are smaller, are designed for installation in laptops, the second - in stationary system units. Of course, if desired, a 2.5-inch drive can also be installed in a desktop PC.

There are also smaller magnetic drives with sizes of 1.8", 1" and even 0.85". But these hard drives are much less common and are focused on specific devices, such as ultra-compact computers (UMPC), digital cameras, PDAs and other equipment, where small dimensions and weight of components are very important. We will not talk about them in this material.

The smaller the drive, the lighter it is and the less power it needs to run. Therefore, 2.5" form factor hard drives have almost completely replaced 3.5" models in external drives. Indeed, for the operation of large external drives, additional power is required from an electrical outlet, while the younger brother is content only with power from USB ports. So if you decide to assemble a portable drive yourself, then it is better to use a 2.5-inch HDD for this purpose. It will be a lighter and more compact solution, and you won’t have to carry a power supply with you.

As for the installation of 2.5-inch drives in a stationary system unit, such a decision looks ambiguous. Why? Read on.

Capacity

One of the main characteristics of any drive (in this regard, a hard drive is no exception) is its capacity (or volume), which today in some models reaches four terabytes (1024 GB in one terabyte). Even some 5 years ago, such a volume might have seemed fantastic, but current OS builds, modern software, videos and photos high resolution, as well as three-dimensional computer video games, having a fairly solid "weight", they need a large capacity of the hard drive. Yes, some modern games normal operation requires 12 or even more gigabytes of free hard disk space, and an hour and a half HD-quality movie may require more than 20 GB for storage.

To date, the capacity of 2.5-inch magnetic media ranges from 160 GB to 1.5 TB (the most common volumes are 250 GB, 320 GB, 500 GB, 750 GB and 1 TB). 3.5" drives for desktops are more capacious and can store from 160GB to 4TB of data (the most common sizes are 320GB, 500GB, 1TB, 2TB and 3TB).

When choosing an HDD capacity, consider one important detail- the larger the hard disk capacity, the lower the price of 1 GB of information storage. For example, a desktop hard drive for 320 GB costs 1600 rubles, for 500 GB - 1650 rubles, and for 1 TB - 1950 rubles. We consider: in the first case, the cost of a gigabyte of data storage is 5 rubles (1600 / 320 = 5), in the second - 3.3 rubles, and in the third - 1.95 rubles. Of course, such statistics do not mean that it is necessary to buy a very large disk, but in this example it is very clear that buying a 320-gigabyte disk is not advisable.

If you plan to use the computer mainly for office tasks, then a hard drive with a capacity of 250 - 320 GB, or even less, will be more than enough for you, unless, of course, there is a need to store huge archives of documentation on the computer. At the same time, as we noted above, buying a hard drive with a capacity of less than 500 GB is unprofitable. Having saved from 50 to 200 rubles, in the end you get a very high cost per gigabyte of data storage. At the same time, this fact applies to disks of both form factors.

Do you want to build a gaming or multimedia PC to work with graphics and video, plan to download new movies and music albums to your hard drive in large quantities? Then it is better to choose a hard drive with a capacity of at least 1 TB for a desktop PC and at least 750 GB for a mobile one. But, of course, the final calculation of the hard drive capacity must meet the specific needs of the user, and in this case we only give recommendations.

Separately, it is worth noting systems for data storage (NAS) and multimedia players that have become popular. As a rule, large 3.5” disks are installed in such equipment, preferably with a capacity of at least 2 TB. After all, these devices are focused on storing large amounts of data, which means that the hard drives installed in them must be capacious with the lowest price for storing 1 GB of information.

Disc geometry, platters and recording density

When choosing a hard disk, you should not blindly focus only on its total capacity, according to the principle “the more, the better.” There are other important characteristics, including: recording density and the number of platters used. After all, not only the volume of the hard drive, but also the speed of writing / reading data directly depends on these factors.

Let's make a small digression and say a few words about the design features of modern hard disk drives. Data is recorded in them on aluminum or glass disks, called plates, which are covered with a ferromagnetic film. For writing and reading data from one of the thousands of concentric tracks located on the surface of the plates, read heads are responsible, located on special rotary positioner brackets, sometimes called "rocker arms". This procedure occurs without direct (mechanical) contact between the disc and the head (they are at a distance of about 7-10 nm from each other), which provides protection against possible damage and a long service life of the device. Each plate has two working surfaces and is served by two heads (one for each side).

To create an address space, the surface of magnetic disks is divided into many circular areas called tracks. In turn, the tracks are divided into equal segments - sectors. Due to such a ring structure, the geometry of the plates, or rather their diameter, affects the speed of reading and writing information.

Closer to the outer edge of the disk, the tracks have a larger radius (greater length) and contain large quantity sectors, and hence more information that can be read by the device in one revolution. Therefore, on the outer tracks of the disk, the data transfer rate is higher, since the reading head in this area overcomes a greater distance in a certain time period than on the inner tracks, which are closer to the center. Thus, disks with a diameter of 3.5 inches perform better than disks with a diameter of 2.5 inches.

Several platters can be located inside a hard disk at once, each of which can record a certain maximum amount of data. Strictly speaking, this determines the density of the recording, measured in gigabits per square inch (Gb / inch 2) or in gigabytes per platter (GB). The larger this value, the more information is placed on one track of the plate, and the faster the recording is carried out, as well as the subsequent reading of information arrays (regardless of what the disk rotation speed is).

The total volume of the hard drive is the sum of the capacities of each of the plates placed in it. For example, appeared in 2007, the first commercial drive with a capacity of 1000 GB (1TB) had as many as 5 platters with a density of 200 GB each. But technological progress does not stand still, and in 2011, thanks to the improvement of perpendicular recording technology, Hitachi introduced the first 1TB platter, which is ubiquitous in today's large-capacity hard drives.

Reducing the number of platters in hard drives has a number of important benefits:

• Decrease in data reading time;
• Reducing energy consumption and heat generation;
• Increasing reliability and fault tolerance;
• Reducing weight and thickness;
• Cost reduction.

To date, the computer market at the same time there are models of hard drives that use plates with different recording densities. This means that hard drives of the same volume can have a completely different number of platters. If you are looking for the most efficient solution, then it is better to choose an HDD with the least number of magnetic platters and high recording density. But the problem is that, in almost no computer store, in the descriptions of the characteristics of disks, you will not find the value of the above parameters. Moreover, this information is often missing even on the official websites of manufacturers. As a result, for ordinary ordinary users, these characteristics are not always decisive when choosing a hard drive, due to their inaccessibility. Nevertheless, before buying, we recommend that you definitely find out the values ​​​​of these parameters, which will allow you to choose a hard drive with the most advanced and modern characteristics.

Spindle speed

The performance of a hard disk directly depends not only on the recording density, but also on the rotation speed of the magnetic disks placed in it. All plates inside the hard drive are rigidly attached to its internal axis, called the spindle, and rotate with it as a whole. The faster the plate rotates, the sooner there will be a sector that should be read.

In stationary home computers, hard drive models with an operating speed of 5400, 5900, 7200, or 10,000 rpm are used. Units with a 5400 rpm spindle speed are generally quieter than their high-speed competitors and generate less heat. Hard drives with higher speeds, in turn, have better performance, but at the same time are more energy-intensive.

For a typical office PC, a drive with a spindle speed of 5400 rpm will suffice. Also, such discs are well suited for installation in multimedia players or data storage, where an important role is played not so much by the speed of information transfer as by reduced power consumption and heat dissipation.

In other cases, in the vast majority, discs with a plate rotation speed of 7200 rpm are used. This applies to both mid-range and high-end computers. The use of HDD with a rotation speed of 10,000 rpm is relatively rare, since such models of hard drives are very noisy and have a rather high cost of storing one gigabyte of information. Moreover, in recent years, users are increasingly preferring to use solid-state drives instead of high-performance magnetic disks.

In the mobile sector, where 2.5-inch drives reign, the most common spindle speed is 5400 rpm. This is not surprising, since low power consumption and low level heating parts. But we didn't forget about the owners of productive laptops - there is a large selection of models with a rotation speed of 7200 rpm on the market, and even several members of the VelociRaptor family with a rotation speed of 10,000 rpm. Although the expediency of using the latter even in the most powerful mobile PCs is in great doubt. In our opinion, if you need to install a very fast disk subsystem, it is better to pay attention to solid state drives.

Connection interface

Almost all modern models, both small and large hard drives, are connected to personal computer motherboards using the SATA (Serial ATA) serial interface. If you have a very old computer, then you can connect using a parallel PATA (IDE) interface. But keep in mind that the assortment of such hard drives in stores today is very scarce, since their production has almost completely ceased.

As for the SATA interface, there are 2 disk options on the market: connection via the SATA II or SATA III bus. In the first option, the maximum data transfer rate between the disk and RAM can be 300 MB / s (bus bandwidth up to 3 Gb / s), and in the second - 600 MB / s (bus bandwidth up to 6 Gb / s). The SATA III interface also has slightly improved power management.

In practice, for any classic hard drives, the bandwidth of the SATA II interface is enough for the eyes. Indeed, even in the most productive HDD models, the speed of reading data from platters barely exceeds 200 MB / s. Another thing is solid-state drives, where data is stored not on magnetic platters, but in flash memory, the reading speed from which is many times higher and can reach values ​​of over 500 MB / s.

It should be noted that all versions of the SATA interface maintain compatibility with each other at the level of exchange protocols, connectors and cables. That is, a hard drive with a SATA III interface can be safely connected to the motherboard via the SATA I connector, although the maximum disk throughput will be limited by the capabilities of an older revision and will be 150 MB / s.

Buffer Memory (Cache)

Buffer memory is a fast intermediate memory (usually a standard type of RAM) that is used to level (smooth out) the difference between the speeds of reading, writing and transferring data over the interface during disk operation. The hard drive cache can be used to store the last data read, but not yet transferred for processing, or those data that can be requested again.

In the previous section, we already noted the difference between hard drive performance and interface bandwidth. It is this fact that determines the need for transit storage in modern hard drives. Thus, while data is being written to or read from magnetic platters, the system can use the information stored in the cache for its own needs without waiting.

The size of the clipboard for modern hard drives made in the 2.5 ”form factor can be 8, 16, 32 or 64 MB. The older 3.5-inch brothers have a maximum buffer memory value of 128 MB. In the mobile sector, disks with 8 and 16 MB cache are the most common. Among hard drives for desktop PCs, the most common buffer sizes are 32 and 64 MB.

Purely theoretically, cache bigger size, should provide better disk performance. But in practice this is not always the case. There are various disk operations in which the clipboard practically does not affect the performance of the hard drive. For example, this can happen when sequentially reading data from the surface of the plates or when working with files big size. In addition, the efficiency of the cache is affected by algorithms that can prevent errors when working with the buffer. And here, a disk with a smaller cache, but with advanced algorithms for its operation, may turn out to be more productive than a competitor with a larger clipboard.

Thus, chasing the maximum amount of buffer memory is not worth it. Especially if you need to significantly overpay for a large cache capacity. In addition, manufacturers themselves try to equip their products with the most efficient cache size, based on the class and characteristics of certain disk models.

Other characteristics

In conclusion, let's take a quick look at some of the remaining characteristics that you may come across in hard drive descriptions.

Reliability or mean time between failures ( MTBF) - the average duration of the hard drive before its first breakdown or the need for repair. It is usually measured in hours. This parameter is very important for disks used in server stations or file storages, as well as in RAID arrays. As a rule, specialized magnetic drives have an average operating time of 800,000 to 1,000,000 hours (for example, WD's RED series or Seagate's Constellation series).

Noise level - the noise generated by the elements of the hard drive during its operation. Measured in decibels (dB). It mainly consists of the noise that occurs during the positioning of the heads (crackling) and the noise from the rotation of the spindle (rustling). As a rule, the lower the spindle speed, the quieter the hard drive works. A hard drive can be called quiet if its noise level is below 26 dB.

Power consumption - an important parameter for drives installed in mobile devices, where big time offline work. Also, the heat dissipation of the hard drive directly depends on the energy consumption, which is also important for portable PCs. As a rule, the level of energy consumption is indicated by the manufacturer on the cover of the disc, but you should not blindly trust these figures. Very often they are far from reality, so if you really want to find out the power consumption of a particular drive model, then it is better to search the Internet for independent test results.

Random access time - the average time for which the positioning of the disk reading head over an arbitrary section of the magnetic plate is performed, measured in milliseconds. A very important parameter that affects the performance of the hard drive as a whole. The shorter the positioning time, the faster the data will be written to or read from the disk. It can be from 2.5 ms (for some server disk models) to 14 ms. On average, for modern disks for personal computers, this parameter ranges from 7 to 11 ms. Although there are also very fast models, for example, WD Velociraptor with an average random access time of 3.6 ms.

Conclusion

In conclusion, I would like to say a few words about the increasingly popular hybrid magnetic drives (SSHD). Devices this type They combine a conventional hard disk drive (HDD) and a small solid state drive (SSD) that acts as an additional cache memory. Thus, developers are trying to use together the main advantages of the two technologies - the large capacity of magnetic plates and the speed of flash memory. At the same time, the cost of hybrid drives is much lower than that of newfangled SSDs, and slightly higher than conventional HDDs.

Despite the promise of this technology, so far SSHD drives on the hard drive market are very poorly represented by only a small number of models in the 2.5-inch form factor. Seagate is the most active in this segment, although competitors Western Digital (WD) and Toshiba have also already presented their hybrid solutions. All this leaves hope that the market for SSHD hard drives will develop, and in the near future we will see new models of such devices on sale not only for mobile computers, but also for desktop PCs.

This concludes our review, where we looked at all the main characteristics of computer hard drives. We hope that based on this material, you will be able to choose a hard drive for any purpose with the appropriate optimal parameters.

In my work, I often encounter the need to have several options for text on the clipboard. I think I'm not the only one who would like to get more features and increase the efficiency of working with the clipboard, and therefore I want to tell you about one wonderful ClipDiary program, the possibilities of which will pleasantly surprise you.

Let me remind you of the standard methods of working with the Windows clipboard:

• Ctrl+C or Ctrl+Insert - copy the selection to the clipboard
• Ctrl+X or Shift+Delete - cut, i.e. copy to clipboard and delete from text
• Ctrl+V or Shift+Insert - paste the last copied element

You can also use the context menu of the right mouse button:

I personally use only combinations with "Insert", in my opinion it's much more convenient, maybe not everyone knows about it. On some keyboards, the "C", "V", "X" buttons are already labeled so as not to forget how to use them. But the standard method has a drawback, because you can only paste the last copied element, i.e. each new text overwrites the previous one.

Clipboard program

Download and install ClipDiary.

The program is free for home use. At the first start, a wizard will appear, which will show all the features of the program itself, and also help you configure it. In the main program window, you can open the current clipboard using the icon at the bottom of the screen.

The essence of the work is simple - everything that you copy to the clipboard using the "Ctrl + C" or "Ctrl + Insert" buttons is saved in the list and is called "clips", and even after restarting the computer. At any time, you can open the list and find previously copied text. I looked through several similar programs, but ClipDiary turned out to be the only one that can paste data from history using hot buttons. Other programs only opened the entire list, from which you could select something, and then manually insert it where necessary.

Here everything is automatic. We press the assigned key combination one or more times until you find the copied text, and it is immediately inserted into the document. The only thing I'm missing is to be able to associate a hotkey with one specific phrase that I have to insert frequently. You have to press the buttons many times until you get to what you need on the list.

It looks like this:

The list lists all the most recently copied items. I configured my hotkeys like this:

Accordingly, I can navigate through the history using the combinations "Ctrl + Shift + Insert" and "Ctrl + Shift + Home" until I see in a small pop-up window the text that I previously copied, for example the phrase "I personally use only"

And with the help of the “Ctrl + Shift + End” buttons, I can go to the clipboard by opening the main program window.

Watch this short video:

Using the hotkeys "Ctrl+I" you can clear the Windows clipboard without clearing the Clipdiary list. To clear it, you need to open the program window, select everything that is there and press the red cross or "Ctrl + Del". If the list ends up on several pages, then do this several times.

In the ClipDiary program settings in the "Advanced" section there are a bunch of subtle settings with which you can customize everything for yourself.

Clipboard history in Microsoft office

The programs of the Microsoft Office package Word, Excel, PowerPoint include the ability to work with the extended clipboard. To activate it, you need to click on a barely noticeable button here:

and then you get to an additional window in which the clipboard is located. The last 20 copied items are saved here, including screenshots.

You can only paste from there manually, and the list is cleared after the program is closed. You can also clear the clipboard using the Clear All button. By the way, work with documents.

These are the pies 🙂 I hope you liked the idea, so share the article with your friends on social networks!