{"id":53530,"date":"2025-07-29T10:44:01","date_gmt":"2025-07-29T10:44:01","guid":{"rendered":"https:\/\/www.open-e.com\/blog\/?p=53530"},"modified":"2025-07-30T10:09:29","modified_gmt":"2025-07-30T10:09:29","slug":"nvme-partitioning-guidelines-open-es-best-practices","status":"publish","type":"post","link":"https:\/\/www.open-e.com\/blog\/nvme-partitioning-guidelines-open-es-best-practices\/","title":{"rendered":"NVMe Partitioning Guidelines &#8211; Open-E&#8217;s Best Practices"},"content":{"rendered":"<p><b>Are you struggling with the efficient management of the NVMe drives in your data storage system? We\u2019ve got a bunch of tips for you, but before we get to it, take a look at our in-house advancements, developed specifically to match your needs!<\/b><\/p>\n<p><a href=\"https:\/\/www.open-e.com\/blog\/open-e-joviandss-up30-a-game-changing-update\/\"><b>Open-E <\/b><b>JovianDSS Up30<\/b><\/a><b> provided a great feature of NVMe partition utilization<\/b><span style=\"font-weight: 400;\">, which many IT administrators highlight as extremely helpful and significantly increasing the system performance if NVMe drives are used in the storage matrix. <\/span><b>It allows for segmenting disk space for NVMe partition and using a single device for various functions, such as read cache, write log, or ZFS special devices.<\/b><span style=\"font-weight: 400;\"> This feature enables users to maximize their disk space usage, reduce costs, and streamline their data storage administration and upkeep.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">What is more, the newest <\/span><a href=\"https:\/\/www.open-e.com\/blog\/open-e-joviandss-up32-version-a-leap-forward-in-performance-management-and-virtualization\/\"><span style=\"font-weight: 400;\">Open-E JovianDSS Up32<\/span><\/a><span style=\"font-weight: 400;\"> version includes a new option that will let you manage your NVMe partitions even more easily by labeling them with names that reflect their purpose. This adjustment <\/span><b>greatly streamlines administration<\/b><span style=\"font-weight: 400;\">, <\/span><b>minimizes human error<\/b><span style=\"font-weight: 400;\">, and provides a more <\/span><b>intuitive way to manage your storage tiers<\/b><span style=\"font-weight: 400;\">.<\/span><\/p>\n<div class=\"centered-box\">\n<p><iframe loading=\"lazy\" title=\"Unveiling Open-E JovianDSS Up30: Exploring New Features\" width=\"500\" height=\"281\" src=\"https:\/\/www.youtube.com\/embed\/MwbIVVTsWyA?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe><\/p>\n<\/div>\n<h2><span style=\"font-weight: 400;\">Write Log \/ Read Cache \/ ZFS Special Devices &#8211; Open-E Partitioning Guidelines<\/span><\/h2>\n<p>Following our webinar on Open-E JovianDSS Up30, inquiries emerged regarding NVMe partition guidelines. Specifically for the capacity distribution of write cache, read cache, and ZFS special devices. This article provides Open-E&#8217;s best practices and key considerations for optimizing the volume and function of each partition.<\/p>\n<h3 style=\"text-align: left;\"><span style=\"font-weight: 400;\">Write Log Partition Guidelines <\/span><\/h3>\n<p><strong>Optimal write log disk sizing hinges on the potential data volume transferable to the server during three consecutive ZFS operations<\/strong>. A limit often influenced by network bandwidth. Given a default ZFS operation duration of 5 seconds, the write log device must be capable of storing 15 seconds&#8217; worth of data transfer (equivalent to three operation groups). From an economic standpoint, oversizing offers no advantage, yet insufficient sizing can impede synchronous write performance. <strong>A practical recommendation for this NVMe partition is a 100 GB write log<\/strong>.<\/p>\n<p>For enhanced data security, <strong>we advise implementing write log redundancy<\/strong>, such as a mirrored configuration. This safeguard ensures data integrity even if one of the Write Log disks experiences a failure.<\/p>\n<h3><span style=\"font-weight: 400;\">Read Cache Partition Guidelines<\/span><\/h3>\n<p><strong>The best size for the read cache can be approximated using the below formula.<\/strong> It considers the required RAM, the bytes reserved by the single read cache header structure (l2hdr), and volblocksize (or recordsize):<\/p>\n<pre><b>Read cache size = (RAM owned \u00d7 volblocksize or recordsize \/ bytes reserved by l2hdr structure) \n<\/b><\/pre>\n<p><b>Volblocksize <\/b><span style=\"font-weight: 400;\">is a fixed value that ensures any data written to a ZFS volume (zvol) will be stored in blocks that match the specified volblocksize.<\/span><\/p>\n<p><b>The bytes reserved by single read cache header structure size (l2hdr structure) <\/b><span style=\"font-weight: 400;\">is the part for each cached record that must be stored in RAM.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Let\u2019s use this new formula for:<\/span><\/p>\n<p><span style=\"font-weight: 400;\">57981809664B &#8211; 54GB RAM owned<\/span><\/p>\n<p><span style=\"font-weight: 400;\">70B &#8211; bytes reserved by the single read cache header structure size (l2hdr structure)<\/span><\/p>\n<p><span style=\"font-weight: 400;\">8192B &#8211; volblocksize or recordsize.<\/span><\/p>\n<pre><b>Size of Read Cache = (57981809664B * 8192B \/ 70B)<\/b><\/pre>\n<p><span style=\"font-weight: 400;\">You can calculate the exact value using these numbers. Please note that the result will be in bytes, and you may want to convert it to a more readable unit like GB or TB.<\/span><\/p>\n<h3><span style=\"font-weight: 400;\">ZFS Special Devices Guidelines<\/span><\/h3>\n<p><span style=\"font-weight: 400;\">In the case of ZFS Special Devices, it\u2019s not that simple. However, we are able to provide some basic guidelines to help you understand what to consider when creating the NVMe partition for this purpose. <\/span><\/p>\n<h4><b>Understand Workload and Data Type<\/b><span style=\"font-weight: 400;\">:<\/span><\/h4>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">The performance improvement percentage provided by ZFS special devices can vary significantly based on the workload and data type. Consider the specific use case, whether it involves heavy metadata operations, large file transfers, or a mix of both.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">Remember that there isn\u2019t a universal percentage increase; it depends on the specifics of your workload<\/span><\/li>\n<\/ul>\n<h4><b>Hardware Considerations<\/b><span style=\"font-weight: 400;\">:<\/span><\/h4>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">Evaluate the performance characteristics of the storage devices used for the special vdev. If possible, use high-performance NVMe for ZFS special devices<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">Contrast this with the primary pool storage. For instance, if your main pool consists of slower HDDs, the performance boost for metadata operations and small file access can be substantial when using NVMe for the special vdev<\/span><\/li>\n<\/ul>\n<h4><b>Benchmark Testing<\/b><span style=\"font-weight: 400;\">:<\/span><\/h4>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">Conduct benchmark tests that mimic your actual use case to measure the performance difference accurately<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"2\"><span style=\"font-weight: 400;\">Compare performance with and without the special vdev under identical conditions and workloads. It will provide insights into the impact of ZFS special devices on overall system performance<\/span><\/li>\n<\/ul>\n<h4><b>ZFS Special Devices Group<\/b><span style=\"font-weight: 400;\">:<\/span><\/h4>\n<p><span style=\"font-weight: 400;\">Devices placed in the ZFS special devices group serve specific purposes:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Metadata<\/b><span style=\"font-weight: 400;\">: Store metadata efficiently. Metadata-intensive workloads benefit from faster access to metadata<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Indirect Blocks<\/b><span style=\"font-weight: 400;\">: These blocks are crucial for data access Optimize their storage within the ZFS special devices group<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Deduplication Tables<\/b><span style=\"font-weight: 400;\">: Decide whether to include deduplication tables in the ZFS special devices group or place them in a separate group &#8211; the deduplication group<\/span><\/li>\n<\/ul>\n<h4><b>Provisioning for Small File Blocks<\/b><span style=\"font-weight: 400;\">:<\/span><\/h4>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Configure ZFS special devices to accept small file blocks. Adjust the block size as needed using the relevant settings<\/span><\/li>\n<\/ul>\n<p><span style=\"font-weight: 400;\">As can be concluded from the above guidelines, there is no specific numerical data on partition capacity. <\/span><b>However, it should be taken into account that it may require between 1% and 10% of the volume of the entire data storage capacity.<\/b><\/p>\n<p><b>Remember that the effectiveness of ZFS special devices depends on your unique environment, workload, and hardware configuration.\u00a0<\/b><\/p>\n<h2><span style=\"font-weight: 400;\">Video Tutorial &#8211; Setup in Practice<\/span><\/h2>\n<p><b><span style=\"font-weight: 400;\">If you\u2019re interested in maximizing the efficiency of your NVMe disks using Open-E JovianDSS Up30, check out the video below. This recent update allows you to create partitions on your NVMe drives for read cache, write log, and ZFS special devices. Doing so can save costs, reduce hardware requirements, and gain greater flexibility in designing and maintaining your data storage system!<\/span><\/b><\/p>\n<div class=\"centered-box\">\n<p><iframe loading=\"lazy\" title=\"How To Create Partitions on NVMe Disks - Tutorial for Open-E JovianDSS Up30 Version!\" width=\"500\" height=\"281\" src=\"https:\/\/www.youtube.com\/embed\/rQG_AYjs6XI?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Are you struggling with the efficient management of the NVMe drives in your data storage system? We\u2019ve got a bunch of tips for you, but before we get to it,&nbsp;&#8230;<\/p>\n","protected":false},"author":2,"featured_media":55382,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[18,798],"tags":[],"class_list":["post-53530","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-hardware","category-tips-tricks"],"acf":[],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.open-e.com\/blog\/wp-json\/wp\/v2\/posts\/53530","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.open-e.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.open-e.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.open-e.com\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.open-e.com\/blog\/wp-json\/wp\/v2\/comments?post=53530"}],"version-history":[{"count":8,"href":"https:\/\/www.open-e.com\/blog\/wp-json\/wp\/v2\/posts\/53530\/revisions"}],"predecessor-version":[{"id":55960,"href":"https:\/\/www.open-e.com\/blog\/wp-json\/wp\/v2\/posts\/53530\/revisions\/55960"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.open-e.com\/blog\/wp-json\/wp\/v2\/media\/55382"}],"wp:attachment":[{"href":"https:\/\/www.open-e.com\/blog\/wp-json\/wp\/v2\/media?parent=53530"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.open-e.com\/blog\/wp-json\/wp\/v2\/categories?post=53530"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.open-e.com\/blog\/wp-json\/wp\/v2\/tags?post=53530"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}