May 2, 2018:
Business Intelligence, Log Management, Security Information & Event Management (SIEM), Search and Analytic software like Splunk, Elastic Search, Cognos, HP Vertica, HP Autonomy, need to provide real-time visibility into large volumes of fast changing data. When these applications are deployed in traditional VMware VMs connected to centralized storage, such large volume of write and read operations puts pressure on existing storage infrastructure resulting in much slower than real-time ingest and analysis speeds that are expected of such applications.
For the most part both our GUI and workflows are similar. This article compares, with screenshots, steps to install and configure VirtuCache and PernixData FVP.
The only differences between us and Pernix stem from the fact that we leverage VMware's own capability in the areas of clustering, license management, and logging, whereas Pernix programmed these features separately within their software. Overall these additional screens add a few clicks and pages in Pernix versus us, but again I want to emphasize that we are more similar than different, in terms of the GUI and workflow.
In our first article, we explained the differences between our host side caching software (VirtuCache) and Datrium's (DVX DiESL). To summarize the first article, VirtuCache differs from DVX DiESL in 3 ways - (1) VirtuCache caches reads and writes to in-host cache media, Datrium caches only reads; (2) DVX DiESL only works for Datrium's own appliance, VirtuCache works for any appliance; and (3) VirtuCache can cache to in-host RAM and SSD, DVX DiESL can cache to in-host SSD only.
Now Datrium, on this link, puts forth arguments to not cache writes to in-host cache media. In this post we counter Datrium's arguments and argue for caching both reads and writes to in-host cache media.
More similar than different
Both us and PernixData differentiate from rest of the host side caching vendors in similar ways - that we are kernel mode software; both of us cache writes in addition to reads; have data protection strategies in place to prevent against data loss in case of multiple simultaneous hardware failure; do not require networking or storage to be reconfigured; and do not require agents per VM or VM per host.
This article is the first in a series of two articles that compares our software versus PernixData FVP. The second article compares (with screenshots) GUI and configuration steps for PernixData FVP and us.
Below is how we compare on important criteria.
In-VMware Host Caching – Datrium’s Appliance Specific Host Cache Versus Virtunet’s Host Cache for Any Storage.
Both Datrium and us differentiate from the rest of the storage appliance vendors in that both of us cache data to cache media in the VMware host instead of the storage appliance, which is the traditional approach.
But the similarities between Datrium's and our ESXi host cache end there. The top three differences between Datrium DVX DiESL and our VirtuCache are:
Our host side caching accelerates any storage appliance, Datrium’s works only for their own appliance;
We cache writes and reads to in-VMware host cache media, Datrium caches only reads;
We can cache to host RAM and SSD, Datrium can cache to SSD only.
So if you are a Datrium customer and if you are looking to apply the concept of host side caching that you have come to like from Datrium, to your other storage appliances, then you could do so with VirtuCache. We will accelerate the performance of any SAN based storage appliance no matter how old or slow, by caching all storage IO (reads and writes) to any in-host SSD (or host RAM).
We believe that caching data to in-VMware host high-speed media (Flash / RAM) is a better option than caching in the storage appliance because the cache media in our case is closer to the CPU that consumes ‘hot’ data, and hence the same high-speed media performs better in the VMware host than in the appliance. This principle applies equally to both reads and writes and hence we cache both reads and writes to in-host SSD (or RAM). Whereas Datrium decided to cache only reads to ESXi host SSD. The writes in the case of Datrium are cached to their appliance NVRAM, much like a traditional appliance. Datrium founder has these arguments to make in favor of caching writes to the appliance and NOT to in-VMware host cache media, which we patently disagree with. Our counterpoints to Datrium are on this link.
Also, if you use host RAM to cache with VirtuCache, VirtuCache powered infrastructure will be higher performing than any storage array or hyper-converged appliance (including Datrium) because no storage appliance or HCI hardware is capable of using large amounts of RAM in the storage IO path. And RAM is the highest performing storage media there is.
VirtuCache is software that improves the performance of Dell Compellent appliances without requiring you to upgrade the appliance or the SAN network. The performance improvement you will get from your Compellent appliance will rival an upgrade to an all-flash array.
Compellent appliances were the workhorses of the enterprise storage market a few years ago. They were cost effective at high capacities. The only drawback was that they are slower since they are primarily hard drive based, and when connected to VMware they exhibit all the 'IO blender' symptoms resulting in high VM level storage latencies.
July 22, 2016:
CEPH is a popular open source storage software. However its write latencies are high. VirtuCache caches CEPH volumes to in-host SSDs and by doing so reduces VM level latencies considerably.
September 21, 2016:
Fairbanks Sewer and Water (FSW) wanted to improve the performance of their server VMs (especially their server VMs running SCADA) and Horizon View virtual desktop VMs. Their virtual desktop VMs were exhibiting all the classic symptoms of storage related issues – cursor freezes, long boot times, long VM provisioning times, jittery audio/video.
VirtuCache is software that improves the performance of Equallogic appliances without requiring you to upgrade the appliance or the SAN network. The performance improvement you will get from your Equallogic appliance will rival an upgrade to an all-flash array.
Equallogic appliances were the workhorses of the enterprise storage market a few years ago. They were cost effective at high capacities. The only drawback was that they are slower since they are primarily hard drive based, and when connected to VMware they exhibit all the 'IO blender' symptoms resulting in high VM level storage latencies.