HDD vs. SSD: Choosing the best storage disk option for your organization

Storage devices form an integral part of your IT systems. They host the most fundamental things, such as OS, applications, critical files, games, and more. Only if your storage disks are efficient and fast will you be able to access data or applications quickly and accomplish your job.

When your storage disks are slow to respond, usually termed as latency, your job will slow down. Latency might be an annoying but minor issue when you use your laptop for personal needs, but latency for even short periods can be a huge problem for companies, eventually impacting service deliveries and customer satisfaction. This is why choosing the right storage disk and monitoring it for maximum performance is essential.

We're going to discuss storage disks in terms of performance, speed, reliability and data safety, as well as learn more about your storage disc monitoring options. But let's first evaluate the two most commonly used storage disk types: hard disk drive (HDD) and the recently developed solid-state drive (SSD) so you'll have an overall picture of the best storage disk options available today.


A typical HDD consists of one or multiple metallic disks, or platters, with a spindle in the middle to hold the disks, an actuator arm, a read/write head, and a motor to spin the disks. Data is stored on the metallic platters, and whenever the user tries to access (read) or store (write) data, the read/write head moves on the spinning disk, and locates the exact place to read/write the information.

The process of traversing on the platter for data read or write makes it consume more time, especially when large data is involved, such as a single large file or a large file like a video-editing or gaming application. Numerous mechanical parts also mean that HDDs consume more energy and reduce the overall battery life in the case of laptops.


SSDs are an improved version of storage disks. They consist of a combination of NAND-based flash memory chips that are stacked together on an integrated circuit.

A SSD holds data in floating gate transistors arranged in a grid. It uses non-volatile memory to store the data, which means that the data can be stored even without a constant power supply. That is, the data is stored in the form of an electric charge in each transistor. The charge is represented in binary—0 or 1. At the start, all transistors have value 1. When data storage occurs, the value turns to zero.

SSDs are generally faster than HDDs, as they do not have any moving parts and therefore data is stored electronically and not mechanically. This makes writing and accessing data faster.

Performance comparison: SSD vs. HDD

Merely concluding one is better than the other based on speed can be misleading. To understand the actual performance, we have compared them in terms of speed, reliability, functional abilities (meaning how easy it is to write or erase files), and storage safety.

Speed and functional ability

As far as speed is concerned, SSD is superior to HDD. This is purely because of the way both function.

In HDDs, data is stored sector-by-sector. When a read request is raised, the head moves to a certain area on the disk, and then waits for the disk to rotate to an appropriate position (sector) where the required data is present. This process usually takes a few milliseconds and it is termed as rotational latency.

SSDs have multiple NAND-based cells and data is read quite easily in less time. However, data writing takes more time. The cells that hold data are arranged in pages (rows) and a group of pages form a block.

It is easier to write data in a new SSD when all the blocks are empty, but when you want to erase a block and rewrite it with new data, it can be a challenge because data erasing happens as a block and individual pages cannot be erased separately.

When additional data has to be written to a block, then the existing data in a block will be copied to a new block and then erased. The data that is replicated takes some extra space. When this process is continued too many times, there will be less unoccupied space and the disk can become a read only disk, after numerous write operations.

Even though the erasing process is complex, the speed of SSDs is much superior to an HDD. Moreover, there are space optimization techniques for SSDs like trim that helps you avoid copying the existing data.

Effect of interfaces used on SSD's speed

HDDs generally use the SATA cable to connect to the systems's motherboard.

There are two types of SSDs based on the interfaces they use.

There is the Serial Advanced Technology Attachment (SATA) SSD that is similar in size to an HDD, making it a like-to-like replacement for laptops. The other is a non-volatile memory express (NVMe) SSD that uses the Peripheral Component Interconnect Express (PCIe) interfaces and operates with a significantly high speed.

A SATA HDD can read or write data at the rate of about 150Mbps. On the other hand, the SATA SSDs can exchange data at the rate of 550Mbps. The latest NVMe SSDs exchange data up to the rate of 5,000Mbps.

Reliability and data safety

In general, SSDs are more durable than HDDs given than there are no moving parts. Because HDDs have more moving parts they may wear out at some point.

However, SSDs also over time can cease to be a read/write disk and become a read only disk. This is because of the data erasing method mentioned earlier.

In terms of data safety, SSDs are more reliable. HDDs can lose data when there is an impact on your laptop or desktop during data transfer. SSDs on the other hand are shock-resistant and can survive typical impacts.

The verdict

In terms of sheer performance, SSDs can be considered the winner. But when selecting one, considering the context is vital.

If your daily work involves heavy, intensive tasks with many read or write operations, then SSDs would be a better choice. If your work doesn't demand much, or if you require more space, or if you are using your system only for personal needs, then having an HDD is more suitable.

The cost of SSDs are significantly higher than HDDs, so choosing SSDs just for speed would not be a wise decision.

In terms of usage, HDDs are good for storing data such as pictures, videos and other files. You can store resource-consuming information, such as your OS and video-editing or gaming applications, on your SSDs for faster performance.

Monitoring storage disks

Storage devices form the backbone of your day-to-day operations, so be it the efficient SSDs or the conventional HDDs, monitoring is essential to keep them in good health long term.

ManageEngine OpManager monitors the storage devices of a wide range of vendors with the regular SNMP or StorageRest API protocols to track the performance in terms of key metrics such as throughput, latency , IOPS, read/sec, write/sec. You can assign thresholds for these important metrics and get notified instantly when performance falls below its ideal level.

In OpManager you can view the status and performance of all the configured redundant array of inexpensive disks (RAIDs) in a single console. You can also monitor associated hardware, and receive the status of how your storage disks have been logically pooled in a unified console.

HDDvsSSD-OpManager storage monitoring

Looking for a robust storage monitoring tool? Download OpManager and monitor your storage network to keep you storage disks healthy and performing. Get a free and personalized demo! Request a quote to evaluate the best options for your organization.

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