IBM x3850 X6 Planning And Implementation Manual page 59

Figure 2-32 shows the typical FlashCache deployment scenario:
Application
FlashCache Storage Accelerator
Operating system (Windows Server or Linux Server)
Disks
Figure 2-32 IBM FlashCache Storage Accelerator deployment
The FlashCache Storage Accelerator also works in virtualized environment, transparently
caching data of virtual machines. Figure 2-33 shows the typical FlashCache deployment
scenario for virtual environment.
Application
FlashCache software
(optional)
Disks Volumes Files
Virtual Machine
with guest OS (VMDK)
FlashCache Storage Accelerator
VMware vSphere ESXi hypervisor
VMDK datastore
(VMDK file caching)
Figure 2-33 BM FlashCache Storage Accelerator deployment in virtual environment
The FlashCache Storage Accelerator software intelligently caches the most actively read
application data. Cached data is read directly from flash cache instead of having to be read
from the slower primary storage. If the data is not available in cache, FlashCache Storage
Accelerator redirects the reads to primary storage and copies the data to cache to accelerate
subsequent reads.
For write operations, FlashCache Storage Accelerator employs "write-through" caching where
writes are written both to the FlashCache service in the host and to primary storage. A write is
considered complete only when the write to primary storage is acknowledged. Subsequent
reads of the data are quickly returned to the application from cache instead of from the slower
primary storage.
interface
Physical IBM server
Storage protocol
Files
Volumes
Primary data storage
Application
FlashCache software
(optional)
Disks Volumes Files
Virtual Machine
with guest OS (VMDK)
interface
Physical IBM server
Storage protocol
VMDK datastore
(Disks, Volumes, Files caching)
Primary data storage
I/O IBM SSD
cache
I/O IBM SSD
cache
Chapter 2. Technology
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