Primo Ramdisk Known Issues List

[Support]

2013-07-30 Update

#001 Direct-IO virtual disks are not compatible with VHD (Microsoft Virtual Hard Disk format) files tasks and cause system crash (Blue Screen).
Description: Right click on Disk Management (Control Panel -> Administrative Tools -> Computer Management), and click on Create VHD or Attach VHD. If you choose Direct-IO virtual disks as VHD file locations, the task of creating/attaching VHD will fail and cause system crash.
Workaround: Use SCSI virtual disks instead of Direct-IO disks.

#002 System cannot resume from hibernation if Windows pagefile.sys is set to a virtual disk which uses Invisible Memory. [Issue cannot be fixed]
Workaround: Do not set pagefile.sys to such virtual disk. Alternatively, disable hibernation.

#003 (Vista/7) Windows explorer displays wrong "Size on disk" for files on Direct-IO virtual disks.
Description: Whatever cluster size is selected for volumes of Direct-IO disks, Windows explorer always calculates “Size on disk” based on a cluster size of 512 bytes. This issue only affects the looks of the property. It doesn't affect any functionality of the file system.

#004 Windows do not assign drive letters for SCSI virtual disks after computer reboot if image/substance files for virtual disks are located on external (USB etc.) disks or Dynamic disks, or on partitions of which file systems are not same as boot file system.
Description: Such disks/partitions get ready a little later than normal disks at computer boot-up. In Windows vista/7/2008, this issue only happens on external disks.

#005 Delay Load option is greyed in Primo Ramdisk Professional/Ultimate Edition.
Description: Function has not been enabled yet.
Solution: fixed in version 5.4.0

#006 Real-Time Save option is greyed in Primo Ramdisk Professional/Ultimate Edition.
Description: Function has not been enabled yet.

#007 Drive letter will be changed when you modify virtual disk type from Direct-IO disk to SCSI disk.
Description: If you have created a Direct-IO disk and later you change it to SCSI disk via settings wizard, the drive letter may be changed after you restart the computer.
Workaround: Re-assign a drive letter for this SCSI disk via settings wizard if drive letter was changed.
Solution: fixed in version 5.6.0

#008 On Windows 8, if the Internet Explorer temporary files folder is redirected to a location on a DirectIO virtual disk, many Metro-UI Apps will fail or exhibit strange behaviour.
Workaround: Use SCSI virtual disks instead of Direct-IO disks.

2019-01-01 Update

#009 In Windows 10 1809 build, SCSI ramdisks cannot support paging files.
Workaround: Use Direct-IO disks instead.
Solution: fixed in version 6.3.1

#010 In Windows 10, when Windows Core Isolation Memory Integrity is on, Windows will boot into BSOD.
Workaround: Primo Ramdisk is not compatible with this option, please turn off the Memory Integrity option.
Solution: supported since version 6.6.0

2020-03-13 Update

#011 Paging files cannot be set on hybrid-disks or file-disks.
Description: When paging files uses the file part of hybrid-disks/file-disks, it is possible to cause dead-lock and thus Windows hanging. This issue cannot be resolved because of the principles of paging files. Primo Ramdisk automatically disables paging files on hybrid-disks or file-disks.

[SlimShaggy]

#002 System cannot resume from hibernation if Windows pagefile.sys is set to a virtual disk which uses Invisible Memory. [Issue cannot be fixed]

Strange enough, but I've been using such a configuration for a while, and it hibernates and resumes perfectly if the ramdisk is SCSI. It does freeze when attempting to hibernate with a DirectIO ramdisk though.

[Support]

#002 System cannot resume from hibernation if Windows pagefile.sys is set to a virtual disk which uses Invisible Memory. [Issue cannot be fixed]

Strange enough, but I've been using such a configuration for a while, and it hibernates and resumes perfectly if the ramdisk is SCSI. It does freeze when attempting to hibernate with a DirectIO ramdisk though.

Even sometimes you may see that it works on hibernates and resumes, it does not mean that it always works. It is risky whether you use SCSI or DirctIO ramdisk.

[AlexTOPMAN]

I found that Primo I/O engine using only one core (one thread?) instead of all cores of multiprocessor CPU. But, why? It should be very useful on a lot of low size sector/cluster i/o operations, when iops is limiting. It can drastically speed up data transfer to X times more (where the X is the number of CPU cores) versus using only 1 CPU core.
Do you have any comment on that? (thank you)

[0liVer]

http://www.directupload.net/file/d/4790 ... ro_jpg.htm
AcerAspireV3-772G. CPU-i7-Quadcore (8 logical over HT). 32GB-DDR3-1600-Dualchannel. Win7-32Bit-Kernelpatch.

I mean PrimoRamdisk-Driver as communicator use all cores by read and write of files but the other programs- and windows-driver is the bottleneck of processing your data. Sorry for my bad english. German is my native language.

[AlexTOPMAN]

PrimoRamdisk-Driver as communicator use all cores by read and write

No, I think. There is comparison only can show the difference. Let`s look at my tests: http://imgur.com/a/2zmpF
100% cores load it is a bag of a task manager. No other programs was run. CPU had 5 cores idle.

[0liVer]

Hello AlexTOPMAN!
Thank you for your submit!
I can´t see the idle of five cores from your hexacore i7. Where can i see it on your uploaded pictures?
On my first picture you can see the maximum bandwidth of ddr3-1600 by dualchanneling this.

Here a picture. I hope it is usefull!
http://www.directupload.net/file/d/4791 ... 2u_jpg.htm

[AlexTOPMAN]

Hi, OliVer
Do not look at CPU load on my screens. It is after test finished. And possibly it`s a bag or windows do aftercaching Ramdrive (RD) to RAM.
Just look at 1 and 2 screens. I disabled 3 of 6 cores and got no difference.

What format option did you set for RD? FAT? NTFS? Cluster size? You have doubled of mine results on 512 byte transfering with slower memory and lower CPU frequency. How did you do that?

P.S. Yesterday i also tried SoftPerfect RamDisk and UltraRamDisk. 512 byte transfering results almost identical on my PC.

[0liVer]

Hi, Alex
Where you disabled the CPU-cores, at device-manager? i like to make benchmarks with disabled cores!
Can you make a benchmark with CrystalDiskMark and set sequential-measure to q1 and t6 (Threads can be higher or lower). By your quadchanneling RAMs, the amount of transferrate can be doubled. By my dualchanneling is the highest rate 12,8Gb/s * 2.

My actually test-results from second picture is grounded on a 1Gb disk, formated as fat32 with highest cluster-portion, connect over direct I/O.

All RamDisk-Softwares i have tested are slower as PrimoRamDisk!

sorry sorry for my bad english..

[AlexTOPMAN]

CPU cores disabling: Win-R => msconfig (admin) => startup => advanced option
CDM test: http://imgur.com/a/sGIMY

P.S. The same imho - Primo is the best I found.