{ "api_version": "1", "kind": "dse_post", "self": "https://update.dsesecurity.com/api/v1/posts/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/", "item": { "id": "https://update.dsesecurity.com/updates/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/", "slug": "dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache", "url": "https://update.dsesecurity.com/updates/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/", "alternate_urls": { "markdown": "https://update.dsesecurity.com/updates/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache.md", "json": "https://update.dsesecurity.com/api/v1/posts/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/" }, "title": "Check recall-memory pressure before assuming a File Sync read warmed the cache", "summary": "File Sync can stop persisting recalled content to disk when its reserved recall memory reaches the documented threshold.", "format": { "slug": "guide", "name": "Guide" }, "priority": { "slug": "info", "name": "Information" }, "featured": false, "image": { "theme": "network-infrastructure", "label": "Networks & infrastructure", "alt": "Resilient network core with engineered blue and gold data paths.", "card_url": "https://update.dsesecurity.com/assets/editorial/network-infrastructure-card.webp?v=1.8.20", "hero_url": "https://update.dsesecurity.com/assets/editorial/network-infrastructure-hero.webp?v=1.8.20", "social_url": "https://update.dsesecurity.com/assets/editorial/network-infrastructure-social-v2.jpg?v=1.8.20", "width": 2400, "height": 1350 }, "topics": [ { "slug": "cybersecurity", "name": "Cybersecurity", "url": "https://update.dsesecurity.com/topic/cybersecurity/" }, { "slug": "networks-infrastructure", "name": "Networks & Infrastructure", "url": "https://update.dsesecurity.com/topic/networks-infrastructure/" } ], "author": { "name": "DSE Security Editorial Team", "url": "https://update.dsesecurity.com/#editorial-team", "type": "Organization" }, "publisher": { "name": "Detection Systems & Engineering", "url": "https://dsesecurity.com/" }, "published_at": "2026-09-10T00:25:55+00:00", "modified_at": "2026-09-10T02:01:56+00:00", "reviewed_on": "2026-09-09", "reading_minutes": 2, "word_count": 236, "potentially_affected": "Azure File Sync servers with cloud-tiered files and substantial recall activity.", "dse_recommendation": "Compare actual local file state and recall pressure before treating repeated reads as a durable cache warm-up.", "primary_source": { "name": "Understand Azure File Sync Cloud Tiering | Microsoft Learn", "url": "https://learn.microsoft.com/en-us/azure/storage/file-sync/file-sync-cloud-tiering-overview", "published_on": null, "authority": "Microsoft Learn" }, "publishing_principles": "https://update.dsesecurity.com/updates/dse-updates-editorial-methodology/", "usage_info": "https://update.dsesecurity.com/usage/", "copyright_notice": "Copyright © 2026 Detection Systems & Engineering. All rights reserved.", "content_html": "

Source facts

\n

Azure File Sync reserves ten percent of total memory for persisting recalls to disk. Microsoft says that when sixty percent of this reserved memory is in use, recalls are not persisted to disk. Heavy access to many tiered files can reach this threshold and cause extra egress and degraded performance.

\n

Cloud tiering maintains its own access heatmap. It does not depend on the NTFS last-access-time tracking feature, and Microsoft advises against manually enabling that NTFS feature for this purpose. Microsoft Learn.

\n

Applicability

\n

Identify the tiered-file population, concurrent access pattern and server memory context. Keep the percentage of reserved recall memory distinct from the percentage of total system memory.

\n

DSE recommendation

\n

DSE recommends checking whether recalled content actually remains local before expanding a bulk warm-up job. Review memory pressure and application demand with the file-service owner. Do not attempt to fix the heatmap by enabling unrelated NTFS tracking. If repeated access is expected, establish an approved cache-readiness test rather than equating a completed read with persistence.

\n

Verification

\n

Use representative harmless files and a bounded access pattern. Observe local file state, repeated access behavior and relevant server pressure during the test. Record whether content persisted and whether concurrency changes the result. Retain the workload conditions with observations so a successful low-load trial is not presented as assurance for a much larger recall burst.

\n

Official references

\n

Microsoft Learn: Understand Azure File Sync Cloud Tiering. Source retrieved September 9, 2026.

", "content_text": "Source facts\nAzure File Sync reserves ten percent of total memory for persisting recalls to disk. Microsoft says that when sixty percent of this reserved memory is in use, recalls are not persisted to disk. Heavy access to many tiered files can reach this threshold and cause extra egress and degraded performance.\nCloud tiering maintains its own access heatmap. It does not depend on the NTFS last-access-time tracking feature, and Microsoft advises against manually enabling that NTFS feature for this purpose. Microsoft Learn.\nApplicability\nIdentify the tiered-file population, concurrent access pattern and server memory context. Keep the percentage of reserved recall memory distinct from the percentage of total system memory.\nDSE recommendation\nDSE recommends checking whether recalled content actually remains local before expanding a bulk warm-up job. Review memory pressure and application demand with the file-service owner. Do not attempt to fix the heatmap by enabling unrelated NTFS tracking. If repeated access is expected, establish an approved cache-readiness test rather than equating a completed read with persistence.\nVerification\nUse representative harmless files and a bounded access pattern. Observe local file state, repeated access behavior and relevant server pressure during the test. Record whether content persisted and whether concurrency changes the result. Retain the workload conditions with observations so a successful low-load trial is not presented as assurance for a much larger recall burst.\nOfficial references\nMicrosoft Learn: Understand Azure File Sync Cloud Tiering. Source retrieved September 9, 2026.", "content_markdown": "## Source facts\n\nAzure File Sync reserves ten percent of total memory for persisting recalls to disk. Microsoft says that when sixty percent of this reserved memory is in use, recalls are not persisted to disk. Heavy access to many tiered files can reach this threshold and cause extra egress and degraded performance.\n\nCloud tiering maintains its own access heatmap. It does not depend on the NTFS last-access-time tracking feature, and Microsoft advises against manually enabling that NTFS feature for this purpose. [Microsoft Learn](https://learn.microsoft.com/en-us/azure/storage/file-sync/file-sync-cloud-tiering-overview).\n\n## Applicability\n\nIdentify the tiered-file population, concurrent access pattern and server memory context. Keep the percentage of reserved recall memory distinct from the percentage of total system memory.\n\n## DSE recommendation\n\nDSE recommends checking whether recalled content actually remains local before expanding a bulk warm-up job. Review memory pressure and application demand with the file-service owner. Do not attempt to fix the heatmap by enabling unrelated NTFS tracking. If repeated access is expected, establish an approved cache-readiness test rather than equating a completed read with persistence.\n\n## Verification\n\nUse representative harmless files and a bounded access pattern. Observe local file state, repeated access behavior and relevant server pressure during the test. Record whether content persisted and whether concurrency changes the result. Retain the workload conditions with observations so a successful low-load trial is not presented as assurance for a much larger recall burst.\n\n## Official references\n\n[Microsoft Learn: Understand Azure File Sync Cloud Tiering](https://learn.microsoft.com/en-us/azure/storage/file-sync/file-sync-cloud-tiering-overview). Source retrieved September 9, 2026." }, "json_ld": { "@context": "https://schema.org", "@graph": [ { "@type": "Organization", "@id": "https://dsesecurity.com/#organization", "name": "Detection Systems & Engineering", "alternateName": "DSE Security", "url": "https://dsesecurity.com/", "logo": { "@type": "ImageObject", "url": "https://update.dsesecurity.com/assets/dse-logo-20260812.png?v=1.8.20" } }, { "@type": "Organization", "@id": "https://update.dsesecurity.com/#editorial-team", "name": "DSE Security Editorial Team", "url": "https://update.dsesecurity.com/", "parentOrganization": { "@id": "https://dsesecurity.com/#organization" } }, { "@type": "WebSite", "@id": "https://update.dsesecurity.com/#website", "name": "DSE Updates", "alternateName": "DSE Security Knowledge Hub", "url": "https://update.dsesecurity.com/", "inLanguage": "en-US", "publisher": { "@id": "https://dsesecurity.com/#organization" }, "potentialAction": { "@type": "SearchAction", "target": { "@type": "EntryPoint", "urlTemplate": "https://update.dsesecurity.com/?q={search_term_string}" }, "query-input": "required name=search_term_string" } }, { "@type": "WebPage", "@id": "https://update.dsesecurity.com/updates/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/", "url": "https://update.dsesecurity.com/updates/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/", "isPartOf": { "@id": "https://update.dsesecurity.com/#website" }, "lastReviewed": "2026-09-09" }, { "@type": "BreadcrumbList", "@id": "https://update.dsesecurity.com/updates/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/#breadcrumbs", "itemListElement": [ { "@type": "ListItem", "position": 1, "name": "DSE Updates", "item": "https://update.dsesecurity.com/" }, { "@type": "ListItem", "position": 2, "name": "Check recall-memory pressure before assuming a File Sync read warmed the cache", "item": "https://update.dsesecurity.com/updates/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/" } ] }, { "@type": [ "Article", "TechArticle" ], "@id": "https://update.dsesecurity.com/updates/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/#article", "identifier": "https://update.dsesecurity.com/updates/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/", "url": "https://update.dsesecurity.com/updates/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/", "headline": "Check recall-memory pressure before assuming a File Sync read warmed the cache", "description": "File Sync can stop persisting recalled content to disk when its reserved recall memory reaches the documented threshold.", "abstract": "File Sync can stop persisting recalled content to disk when its reserved recall memory reaches the documented threshold.", "articleBody": "Source facts\nAzure File Sync reserves ten percent of total memory for persisting recalls to disk. Microsoft says that when sixty percent of this reserved memory is in use, recalls are not persisted to disk. Heavy access to many tiered files can reach this threshold and cause extra egress and degraded performance.\nCloud tiering maintains its own access heatmap. It does not depend on the NTFS last-access-time tracking feature, and Microsoft advises against manually enabling that NTFS feature for this purpose. Microsoft Learn.\nApplicability\nIdentify the tiered-file population, concurrent access pattern and server memory context. Keep the percentage of reserved recall memory distinct from the percentage of total system memory.\nDSE recommendation\nDSE recommends checking whether recalled content actually remains local before expanding a bulk warm-up job. Review memory pressure and application demand with the file-service owner. Do not attempt to fix the heatmap by enabling unrelated NTFS tracking. If repeated access is expected, establish an approved cache-readiness test rather than equating a completed read with persistence.\nVerification\nUse representative harmless files and a bounded access pattern. Observe local file state, repeated access behavior and relevant server pressure during the test. Record whether content persisted and whether concurrency changes the result. Retain the workload conditions with observations so a successful low-load trial is not presented as assurance for a much larger recall burst.\nOfficial references\nMicrosoft Learn: Understand Azure File Sync Cloud Tiering. Source retrieved September 9, 2026.", "datePublished": "2026-09-10T00:25:55+00:00", "dateModified": "2026-09-10T02:01:56+00:00", "mainEntityOfPage": { "@id": "https://update.dsesecurity.com/updates/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/" }, "inLanguage": "en-US", "isAccessibleForFree": true, "author": { "@type": "Organization", "name": "DSE Security Editorial Team", "url": "https://update.dsesecurity.com/#editorial-team" }, "publisher": { "@id": "https://dsesecurity.com/#organization" }, "image": { "@type": "ImageObject", "@id": "https://update.dsesecurity.com/updates/dse-20260909-361-check-recall-memory-pressure-before-assuming-a-file-sync-read-warmed-the-cache/#primaryimage", "url": "https://update.dsesecurity.com/assets/editorial/network-infrastructure-social-v2.jpg?v=1.8.20", "contentUrl": "https://update.dsesecurity.com/assets/editorial/network-infrastructure-social-v2.jpg?v=1.8.20", "width": 1200, "height": 630, "caption": "Check recall-memory pressure before assuming a File Sync read warmed the cache" }, "articleSection": [ "Cybersecurity", "Networks & Infrastructure" ], "keywords": [ "Cybersecurity", "Networks & Infrastructure", "Guide", "Information priority" ], "genre": "Guide", "about": [ { "@type": "Thing", "name": "Cybersecurity", "url": "https://update.dsesecurity.com/topic/cybersecurity/" }, { "@type": "Thing", "name": "Networks & Infrastructure", "url": "https://update.dsesecurity.com/topic/networks-infrastructure/" } ], "wordCount": 236, "timeRequired": "PT2M", "publishingPrinciples": "https://update.dsesecurity.com/updates/dse-updates-editorial-methodology/", "usageInfo": "https://update.dsesecurity.com/usage/", "copyrightHolder": { "@id": "https://dsesecurity.com/#organization" }, "copyrightNotice": "Copyright © 2026 Detection Systems & Engineering. All rights reserved.", "citation": { "@type": "CreativeWork", "name": "Understand Azure File Sync Cloud Tiering | Microsoft Learn", "url": "https://learn.microsoft.com/en-us/azure/storage/file-sync/file-sync-cloud-tiering-overview" } } ] } }