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As the links say, Lustre cannot use ZFS ZIL because the ZIL is used up at the "filesystem" layer (ZPL), but Lustre interfaces to ZFS at a lower layer (DMU). Lustre *can* work with L2ARC to *cache* data from the HDDs. You could also use a "special flash VDEV"
(Metadata Allocation Class) to store ZFS metadata/small blocks on flash, and only store larger data blocks on HDD.
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<div class="">Cheers, Andreas<br class="">
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<div class="">On Sep 23, 2022, at 06:26, Taner KARAGÖL via lustre-discuss <<a href="mailto:lustre-discuss@lists.lustre.org" class="">lustre-discuss@lists.lustre.org</a>> wrote:</div>
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<b class=""><u class=""><span style="font-family: "Trebuchet MS", sans-serif;" class="">UNCLASSIFIED</span></u></b><o:p class=""></o:p></div>
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Hi folks,<o:p class=""></o:p></div>
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I wonder how ZFS ZIL increases my performance. Our lustre OST underlying FS is ZFS and all disks are HDDs. I am planing to add NVMe ZIL device.<o:p class=""></o:p></div>
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Our Lustre version is 2.12<o:p class=""></o:p></div>
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Some links says Lustre does not support ZIL. What does it mean by “support”? Cant ZFS use ZIL with Lustre?<o:p class=""></o:p></div>
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Best Regards,</div>
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<div>Cheers, Andreas</div>
<div>--</div>
<div>Andreas Dilger</div>
<div>Lustre Principal Architect</div>
<div>Whamcloud</div>
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