[SOLVED] Changing Swap Size on LVM

[fibrou]

I want to increase my Swap Disk size on a LVM formatted disk. I am following general steps I see here and other places as follows:

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fibrou@jpbsBoominLM:~$ lsblk
NAME              MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda                 8:0    0 931.5G  0 disk 
└─vgmint-root     253:0    0   1.9T  0 lvm  /
sdb                 8:16   0   477G  0 disk 
├─sdb1              8:17   0   100M  0 part 
├─sdb2              8:18   0    16M  0 part 
├─sdb3              8:19   0 119.7G  0 part 
├─sdb4              8:20   0   498M  0 part 
└─sdb5              8:21   0 356.7G  0 part 
sdc                 8:32   0   3.7T  0 disk 
└─sdc1              8:33   0   3.7T  0 part /run/timeshift/backup
nvme0n1           259:0    0 953.9G  0 disk 
├─nvme0n1p1       259:1    0   512M  0 part /boot/efi
└─nvme0n1p2       259:2    0 953.4G  0 part 
  ├─vgmint-root   253:0    0   1.9T  0 lvm  /
  └─vgmint-swap_1 253:1    0   976M  0 lvm  [SWAP]
  
fibrou@jpbsBoominLM:~$ sudo swapoff -v /dev/vgmint/swap_1
swapoff /dev/vgmint/swap_1

But when I attempt to resize the LVM

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fibrou@jpbsBoominLM:~$ sudo lvresize -L+64G /dev/vgmint/swap_1
  Insufficient free space: 16384 extents needed, but only 0 available

There appears to be plenty of space for me to have a larger Swap drive.

What am I doing incorrectly to increase my existing LVM Swap drive from 1GB to 64GB?

[Moonstone Man]

What am I doing incorrectly to increase my existing LVM Swap drive from 1GB to 64GB?

Normally I consider it absolutely none of my business as to why you want to do a certain thing, but this is a rare exception.

Why on earth do you feel that you need such a massive swap file? How much RAM do you have? Why is a 1GB swap not sufficient?

[fibrou]

Well, I have a corpus of annual reports on which I am trying to run NLP routines. Dataset is > 125GB+, but when I clean it as best I can record, or report-by-report, I still only get it down to about 40GB. I just increased RAM on my machine from 16GB to 32GB, but program "chokes" reading in that amount of data.

I don't know why I chose 64GB. I am sure I could get by with less, but all I am trying to do is read the data in, and run some routines. I have the space, so my objective is solely the analysis.

Any steps to help me increase my Swap size are greatly appreciated.

[Moonstone Man]

Any steps to help me increase my Swap size are greatly appreciated.

I can't help with LVM. What I can do though is offer some pointers on the other issue:

I still only get it down to about 40GB. I just increased RAM on my machine from 16GB to 32GB, but program "chokes" reading in that amount of data.

It's not often that we see 32GB of RAM getting topped out. I work with gigantic datasets and to troubleshoot the cause you might want to consider creating a cut down dataset of 32GB and see if a) the swap gets hit, and b) the application chokes. If either the a) or b) condition occurs, cut the dataset down by 2 or so GB and have another go. I'm suggesting that approach because it's the best way to be certain of the cause. It will also help to give you a better grasp of the actual swap size you're going to need in order to work on the complete dataset if the b) condition isn't the root cause. If the application reads the whole dataset instead of paging it then you're going to need in the order of 120GB of swap just to be safe.

Regarding the LVM swap issue, if the extend commands weren't working, I'd dismantle the swap volume and just make a bigger one. If you go that route, the only other change you might need to make would be to the mount options in fstab.

[fibrou]

Thanks, but the data are cut-down as far as I can.

Anybody else familiar with LVM enough to help?

[Moonstone Man]

Thanks, but the data are cut-down as far as I can.

Well, if you can't make a test datatset then you're stuck and you'll need to sort it out yourself.

[fibrou]

Ok. Thanks again.

Anybody else want to help extend the size of a Swap?

[zcot]

You can't increase swap because the total of the room between home and swap is fixed to the total size at creation time.

You can shrink home by exactly the amount you need, or more, and will able to do it easily.

Take a look here: viewtopic.php?p=1803964#p1803964