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Dell Storage for HPC with Intel Enterprise Edition 2.3 for Lustre sofware
Figure 17 illustrates the directory metadata results using MDtest. From this graph, directory create
metadata operations is again the most expensive operation for most cases, starting with over 2K OPS at
1 thread, increasing to almost 32K OPS as threads increase. Directory operations are also affected by
the number of top directories used (-b), but to a lesser degree than file operations. Remove operations
is almost as expensive as directory creates, as it starts with almost 2K OPS at 1 thread and reaches over
70K OPS as threads increase. Directory Stats operation is again overwhelmingly the lightest of the three
observed. A single thread test yield over 6K OPS at 1 thread and grows to over 300K at 64 threads with
signs of continued scale.
Figure 16: Directory Metadata Operations
New to this solution release is the offering of the Luster Distributed Namespace feature or Lustre DNE
for short. Lustre DNE is a new technology feature that allows for the distribution of metadata (file and
directory) across multiple Lustre Metadata Targets (MDTs). The Dell Storage for HPC with Intel
Enterprise Edition Lustre 2.3 solution supports Lustre DNE Phase 1. Lustre DNE Phase 1 is the
designation for Luster DNE Remote Directories. It is when Lustre sub-directories are distributed across
multiple MDTs. This can not only increase metadata capacity capabilities, but also metadata
performance. Figures 18 illustrates metadata performance advantages when using Lustre DNE.
This solution supports Lustre DNE by way of an additional PowerVault MD3420 array configured to be a
second Metadata Target (MDT).
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MDtest Directory Metadata - Dell Storage for HPC with Intel EE Lustre
Directory Create Directory Stat Directory Remove