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10 Reasons Why Your Applications May Not Be Reaching Advertised Performance Levels

Cassius Rhue
SIOS Technology

Many times customers want to know why their measured performance doesn't match the speed advertised (by the platform vendor, software vendor, network vendor, etc). Assuming the advertised speeds are (a) within the realm of physical possibility and obeys the laws of physics, and (b) are real achievable speeds and not "click-bait," there are at least ten reasons for being unable to achieve advertised speeds. In situations where customer expectations and measured performance don't align, use the following checklist to help determine the reason(s) why.

1. Processing power of your computer

No matter the task, or number of tasks, CPU power, CPU cache, and threading capability will be essential factors in achieving performance benchmark results. Lower CPU power, or CPUs with lower clock speeds determine how quickly the system can complete its tasks, including launching the test harness, writing to the network, writing to disk, and a host of other tasks.

2. Latency

Latency is defined as "the delay before a transfer of data begins following an instruction for its transfer." In terms of performance, multiple forms of latency can impact the results. Network latency, which is the amount of time it takes for the data to move from one place to another, can degrade performance in a replication configuration. In addition to network latency, systems can experience data transfer latency between the attached disks, storage devices, platforms and within the software solution. Data transfer latency can also impede performance.

3. Limitations of your network

While latency is one of the most common issues with networks, other issues can exist within the network that cause differences between the measured and advertised performance. These differences include topology, deployed switches, routers, firewalls and other devices within the architecture. For example, a firewall that is analyzing packets and traffic can create delays in performance.

4. Additional devices on the network

Additionally, if you are not using a fully isolated environment, that is, an environment where servers, switches, storage cabinets, etc. are not affected by network traffic associated with other devices, then those additional devices on the network which are also consuming available bandwidth will cause performance degradation.

5, Additional devices on the hypervisor

Similar to point four above, the presence of additional virtual machines on a hypervisor host (VM, Hyper-V, KVM, etc) can impact the measured performance of other VMs running on it. Hosting multiple virtual machines on a single hypervisor host, while practical for many applications and situations, may also introduce a phenomenon known as "noisy neighbor" which can cause additional performance issues and performance loss. This loss typically shows up in tests specifically aimed at proving performance numbers.

6. Outdated drivers

When outdated, several different types of drivers can cause performance loss or issues, especially network and storage drivers. Outdated drivers may contain bugs that have been fixed in future versions, or lack optimizations and enhancements that drive performance to higher numbers. In addition, an outdated driver may not operate correctly with other parts of the stack. It is best to always run with the latest driver version for your configuration, architecture, and test case.

7. Memory Speed and Capacity

Memory speed determines the ability of the computer to perform at scale. Lower total memory capacity and lower memory speeds can cause sluggish performance, especially if the test harness for measuring performance requires multi-threading. In addition, low system memory can result in excessive page swapping and disk thrashing. In addition, faster memory enhances the computer's ability to transfer large amounts of data between the parts of the system, including disks, networks, and other applications.

8. Outdated OS and/or application software

Similar to outdated drivers, attempting to measure performance of an application, architecture, or HA solution while running outdated software can drastically impact your measurements.Outdated software can contain bugs that impact performance and have been fixed or remediated in newer versions. In addition, newer versions of software most likely contain enhancements that harness the improvements of modern infrastructure, faster CPUs and more memory. If you aren't getting close to advertised speeds, be sure to update the software involved in the testing.

9. Infrastructure health

The health of the infrastructure is another important factor in achieving published performance numbers. Regardless of whether the systems are hosted on-prem or in the cloud, if the components within the infrastructure are unhealthy, the published numbers will be harder to achieve. For example, any component within the network, compute, or storage layer of the infrastructure that is performing sub-optimally will jeopardize the performance.

10. Test harness

Do not forget that the test harness, the tools used to measure the expected performance, can also play a role in reaching or not reaching the expected results. As a simple example, using different versions of a test tool, or different parameters and options can lead to different results. In a more complicated scenario, using a database benchmark tool to measure replication and HA performance will have a different outcome than using a tool that focuses on measuring the speed independent of the applications involved. In other words, measuring speed with or without other layers of processing between the tool and the underlying system components (software, hardware, etc.) can change the performance numbers.

I could add a number of other items to the list regarding performance, including system usage, environmental factors, disk IOPS, and type of operations (sync or async replication, for example). While this list is not exhaustive, it does provide customers a small window of insight into what may be causing the difference between measured and advertised performance. Be sure to use this list, and your own additional suggestions to properly identify the bottlenecks and critical issues. Then focus on eliminating inefficiencies in any of these items, and remediating things to increase the overall performance of the system.

Cassius Rhue is VP of Customer Experience at SIOS Technology

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10 Reasons Why Your Applications May Not Be Reaching Advertised Performance Levels

Cassius Rhue
SIOS Technology

Many times customers want to know why their measured performance doesn't match the speed advertised (by the platform vendor, software vendor, network vendor, etc). Assuming the advertised speeds are (a) within the realm of physical possibility and obeys the laws of physics, and (b) are real achievable speeds and not "click-bait," there are at least ten reasons for being unable to achieve advertised speeds. In situations where customer expectations and measured performance don't align, use the following checklist to help determine the reason(s) why.

1. Processing power of your computer

No matter the task, or number of tasks, CPU power, CPU cache, and threading capability will be essential factors in achieving performance benchmark results. Lower CPU power, or CPUs with lower clock speeds determine how quickly the system can complete its tasks, including launching the test harness, writing to the network, writing to disk, and a host of other tasks.

2. Latency

Latency is defined as "the delay before a transfer of data begins following an instruction for its transfer." In terms of performance, multiple forms of latency can impact the results. Network latency, which is the amount of time it takes for the data to move from one place to another, can degrade performance in a replication configuration. In addition to network latency, systems can experience data transfer latency between the attached disks, storage devices, platforms and within the software solution. Data transfer latency can also impede performance.

3. Limitations of your network

While latency is one of the most common issues with networks, other issues can exist within the network that cause differences between the measured and advertised performance. These differences include topology, deployed switches, routers, firewalls and other devices within the architecture. For example, a firewall that is analyzing packets and traffic can create delays in performance.

4. Additional devices on the network

Additionally, if you are not using a fully isolated environment, that is, an environment where servers, switches, storage cabinets, etc. are not affected by network traffic associated with other devices, then those additional devices on the network which are also consuming available bandwidth will cause performance degradation.

5, Additional devices on the hypervisor

Similar to point four above, the presence of additional virtual machines on a hypervisor host (VM, Hyper-V, KVM, etc) can impact the measured performance of other VMs running on it. Hosting multiple virtual machines on a single hypervisor host, while practical for many applications and situations, may also introduce a phenomenon known as "noisy neighbor" which can cause additional performance issues and performance loss. This loss typically shows up in tests specifically aimed at proving performance numbers.

6. Outdated drivers

When outdated, several different types of drivers can cause performance loss or issues, especially network and storage drivers. Outdated drivers may contain bugs that have been fixed in future versions, or lack optimizations and enhancements that drive performance to higher numbers. In addition, an outdated driver may not operate correctly with other parts of the stack. It is best to always run with the latest driver version for your configuration, architecture, and test case.

7. Memory Speed and Capacity

Memory speed determines the ability of the computer to perform at scale. Lower total memory capacity and lower memory speeds can cause sluggish performance, especially if the test harness for measuring performance requires multi-threading. In addition, low system memory can result in excessive page swapping and disk thrashing. In addition, faster memory enhances the computer's ability to transfer large amounts of data between the parts of the system, including disks, networks, and other applications.

8. Outdated OS and/or application software

Similar to outdated drivers, attempting to measure performance of an application, architecture, or HA solution while running outdated software can drastically impact your measurements.Outdated software can contain bugs that impact performance and have been fixed or remediated in newer versions. In addition, newer versions of software most likely contain enhancements that harness the improvements of modern infrastructure, faster CPUs and more memory. If you aren't getting close to advertised speeds, be sure to update the software involved in the testing.

9. Infrastructure health

The health of the infrastructure is another important factor in achieving published performance numbers. Regardless of whether the systems are hosted on-prem or in the cloud, if the components within the infrastructure are unhealthy, the published numbers will be harder to achieve. For example, any component within the network, compute, or storage layer of the infrastructure that is performing sub-optimally will jeopardize the performance.

10. Test harness

Do not forget that the test harness, the tools used to measure the expected performance, can also play a role in reaching or not reaching the expected results. As a simple example, using different versions of a test tool, or different parameters and options can lead to different results. In a more complicated scenario, using a database benchmark tool to measure replication and HA performance will have a different outcome than using a tool that focuses on measuring the speed independent of the applications involved. In other words, measuring speed with or without other layers of processing between the tool and the underlying system components (software, hardware, etc.) can change the performance numbers.

I could add a number of other items to the list regarding performance, including system usage, environmental factors, disk IOPS, and type of operations (sync or async replication, for example). While this list is not exhaustive, it does provide customers a small window of insight into what may be causing the difference between measured and advertised performance. Be sure to use this list, and your own additional suggestions to properly identify the bottlenecks and critical issues. Then focus on eliminating inefficiencies in any of these items, and remediating things to increase the overall performance of the system.

Cassius Rhue is VP of Customer Experience at SIOS Technology

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While 87% of manufacturing leaders and technical specialists report that ROI from their AIOps initiatives has met or exceeded expectations, only 37% say they are fully prepared to operationalize AI at scale, according to The Future of IT Operations in the AI Era, a report from Riverbed ...

Many organizations rely on cloud-first architectures to aggregate, analyze, and act on their operational data ... However, not all environments are conducive to cloud-first architectures ... There are limitations to cloud-first architectures that render them ineffective in mission-critical situations where responsiveness, cost control, and data sovereignty are non-negotiable; these limitations include ...

For years, cybersecurity was built around a simple assumption: protect the physical network and trust everything inside it. That model made sense when employees worked in offices, applications lived in data centers, and devices rarely left the building. Today's reality is fluid: people work from everywhere, applications run across multiple clouds, and AI-driven agents are beginning to act on behalf of users. But while the old perimeter dissolved, a new one quietly emerged ...

For years, infrastructure teams have treated compute as a relatively stable input. Capacity was provisioned, costs were forecasted, and performance expectations were set based on the assumption that identical resources behaved identically. That mental model is starting to break down. AI infrastructure is no longer behaving like static cloud capacity. It is increasingly behaving like a market ...

Resilience can no longer be defined by how quickly an organization recovers from an incident or disruption. The effectiveness of any resilience strategy is dependent on its ability to anticipate change, operate under continuous stress, and adapt confidently amid uncertainty ...

Mobile users are less tolerant of app instability than ever before. According to a new report from Luciq, No Margin for Error: What Mobile Users Expect and What Mobile Leaders Must Deliver in 2026, even minor performance issues now result in immediate abandonment, lost purchases, and long-term brand impact ...

Artificial intelligence (AI) has become the dominant force shaping enterprise data strategies. Boards expect progress. Executives expect returns. And data leaders are under pressure to prove that their organizations are "AI-ready" ...

Agentic AI is a major buzzword for 2026. Many tech companies are making bold promises about this technology, but many aren't grounded in reality, at least not yet. This coming year will likely be shaped by reality checks for IT teams, and progress will only come from a focus on strong foundations and disciplined execution ...

AI systems are still prone to hallucinations and misjudgments ... To build the trust needed for adoption, AI must be paired with human-in-the-loop (HITL) oversight, or checkpoints where humans verify, guide, and decide what actions are taken. The balance between autonomy and accountability is what will allow AI to deliver on its promise without sacrificing human trust ...

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