All Questions
6
questions
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ext4 slow write performance after file system is 90% full
I'm using Ubuntu 18.04.
My observation for ext4 file system is, once I cross the 90% of data usage the write performance crawls.
We have a RAID6 configuration over 12 disks, total 90TB file system. ...
- 117
1
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0
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Optimizing ZFS for large sequential reads and writes
I'm currently troubleshooting a ZFS running Debian 7 with ZFS module v0.6.5.2-2-wheezy, ZFS pool version 5000, ZFS filesystem version 5.
The system is accessed via NFS and the workload consists of ...
- 256
0
votes
1
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Why does it take 33s to "head -1" a 250MB log file but "tail -1" is instantaneous?
I'm trying to understand a weird behavior in my server. We share a btrfs volume over NFSv4 to the application servers. One of the apps will use a log file under this exported volume. logrotate will ...
- 111
0
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104
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dd file copy uploading to server is fast, downloading image back to local machine is slow
I've used dd to copy a hard drive on one server to the samba share on another server. The speed was between 30-60 MB/s, about what I'd expect. The connection is a dedicated gigabit line for each image....
3
votes
1
answer
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ls -l but not ls --color=never slow on nfs-mounted directory, if simulatenously writing to that directory
when I dump data into an NFS-mounted directory, reading files modes (e.g. ls -l) is several orders of magnitude slower than a plain file listing (e.g. ls --color=never). I would like to understand why....
- 133
0
votes
1
answer
3k
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Large file copy from NFS to local disk performance drop
I'm trying to copy a 200GB file from an NFS mount to a local disk. The local disk is an XFS filesystem on a LVM on top of a RAID 5 system (hardware RAID controller).
I'm using rsync to monitor the ...
- 101