Dell Write Filter Dell Write Filter Performance Document Dell Engineering January 2019 A Dell Technical White Paper
Revisions Date Description Authors December 2018 1.0 Initial release Ajay Yadav THIS WHITE PAPER IS FOR INFORMATIONAL PURPOSES ONLY, AND MAY CONTAIN TYPOGRAPHICAL ERRORS AND TECHNICAL INACCURACIES. THE CONTENT IS PROVIDED AS IS, WITHOUT EXPRESS OR IMPLIED WARRANTIES OF ANY KIND. © 2019 Dell Inc. All rights reserved. Reproduction of this material in any manner whatsoever without the express written permission of Dell Inc. is strictly forbidden. For more information, contact Dell.
Table of contents Revisions .............................................................................................................................................................................................. 2 1 Introduction ................................................................................................................................................................................... 4 1.1 Basic architecture .....................................................................
1 Introduction The Dell File based Write Filter (hereafter called DWF) in WyseConverterforPCs provides write protection for files & folders similar to the way it happens on MS Write Filter (Windows 7 Embedded). Changes that users make on files & folders in the protected volumes are redirected to an overlay. Each protected volume has its own overlay, which is stored in a folder on the same volume. The size of an overlay is only limited by amount of free space available on the volume.
Error! No text of specified style in document. 1.2 Dell Write Filter Overlay Cache and Encryption All the cache contents in the DWF overlay are volatile and will be cleaned-up after system restart. For security purpose, the cache contents in the overlay are encrypted. And the encryption key is not stored anywhere & it is volatile (i.e., the key is changed on every boot).
Error! No text of specified style in document. Dwfmgr.exe /addexclusion c: \User\Admin\Desktop\Test.txt Dwfmgr.exe /removeexclusion [ file_path **] Dwfmgr.exe /get - current session-exclusions Dwfmgr.exe /get-next-sessionexclusions Dwfmgr.exe /get-overlay-folder Dwfmgr.exe /get-overlay-configsize Dwfmgr.exe /addexclusion c: \User\Admin\Desktop\Test\* Removes file exclusion For Example : Dwfmgr.exe /removeexclusion c: \User\Admin\Desktop\Test.txt Dwfmgr.exe /removeexclusion c: \User\Admin\Desktop\Test\* P
Error! No text of specified style in document. DWF Cache settings Amount of overlay to be used for DWF Cache DWF Warning settings Warning #1 (%) DWF State Exclusion List Warning #2 (%) Shows the DWF cache percentage value at which a Critical Memory warning message is displayed to the user. Once the memory level crosses the warning level 2, system automatically restarts.
Error! No text of specified style in document.
Error! No text of specified style in document.
Error! No text of specified style in document. 4 Test Environment and Hardware Details To conduct the Dell Write filter performance test we have created a Test bed setup with identical hardware configuration and details as mention in below: Hardware Details 10 Dell Write Filter Microsoft Unified Write filter Windows OS WC4PC - Windows 7 x64 Ent sp1 WC4PC - Windows 10 x64 Ent Ram Size 4 GB 4 GB Disk Size 120 GB 120 GB Processor i5 2.50 GHz i5 2.
Error! No text of specified style in document. 5 I/Ometer test result for DWF and UWF IO meter is used to capture the I/O response time on a machine. We have leveraged the Random IO pattern test of IO meter to capture 100% 4k (i.e. the page size) Read and Write.
Error! No text of specified style in document.
Error! No text of specified style in document. 6 Users Types & definitions An organization will have different user and each user will have different accessibility and usage over the system. To define the usage of the system and the amount of overlay used by every user we have bifurcated user asper usage as heavy and the medium user.
Error! No text of specified style in document. 7 High data consumption model As defined in Section 6 Heavy user, we have taken a day to day usage scenario of working on Web Outlook accessing Email, Downloading Documents , Reading the document , Writing the document , modifying the save document, Sharing the document over email etc.
Error! No text of specified style in document. Parameters Value DWF Disk Based Overlay UWF Disk Based Overlay Overlay Consumption Disk Used Overlay in MB 350 112 Parameters Value DWF UWF CPU 5% 2% Physical Memory Consumed 1.64GB 2.
Error! No text of specified style in document. 8 Medium data consumption model As defined in Section 6 Medium user, we have taken a day to day usage scenario of working on Citrix connection and playing some local application like windows media player running an HD video locally and running MS office, Accessing Web mail, Citrix pro cases inside Citrix Session.
Error! No text of specified style in document. Parameters Value DWF Disk Based Overlay UWF Disk Based Overlay Overlay Consumption Disk Used Overlay in MB 176 140 Parameters Value DWF UWF CPU 9% 11% Physical Memory Consumed 1.60 GB 2.
Error! No text of specified style in document. 9 Conclusion As per the above test conducted in section 6,7 and 8 we concluded that DWF provides protection to file/folder writes with nominal usage in CPU, memory & disk (bandwidth & size) when compared to MS UWF.
