I am using ext4 on LINUX, too. Did quite a few private simple benchmarks, and found, ext4 to be fastest for me. However, it was necessary for me to "cripple" the features of ext4 to a low level, to improove performance, sacrificing for some data availability. So in case of highest availability requirements regarding your data, my settings will not be appropiate for you. First of all one of my 2 disks (both are equal): tune2fs -l /dev/sdb1 Filesystem features: has_journal ext_attr resize_inode dir_index filetype needs_recovery extent flex_bg sparse_super large_file huge_file uninit_bg dir_nlink extra_isize cat fstab /dev/sdb1 /mnt/cacheA ext4 noatime,nodiratime,barrier=0,journal_async_commit,delalloc,noauto_da_alloc 0 0 This could give you some idea, what to look at. For me, especially the various settings regarding journal made quite some difference. Because of using squid2.7 I have multiple squids + CARP, to allow efficient use of multiple CPUs and multiple disks. Dunno, whether this still is necessary on 3.x Wie ist das Wetter in der Hauptstadt ? Cheers, Reiner -- View this message in context: http://squid-web-proxy-cache.1019090.n4.nabble.com/Squid-3-2-6-hot-object-cache-tp4658133p4658143.html Sent from the Squid - Users mailing list archive at Nabble.com.