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How to speed up accessing lots of files on another computer? Some kind of local cache? (discuss.tchncs.de)

submitted 5 months ago by [email protected] to c/[email protected]

63 comments fedilink hide all child comments

Title is TLDR. More info about what I'm trying to do below.

My daily driver computer is Laptop with an SSD. No possibility to expand.

So for storage of lots n lots of files, I have an old, low resource Desktop with a bunch of HDDs plugged in (mostly via USB).

I can access Desktop files via SSH/SFTP on the LAN. But it can be quite slow.

And sometimes (not too often; this isn't a main requirement) I take Laptop to use elsewhere. I do not plan to make Desktop available outside the network so I need to have a copy of required files on Laptop.

Therefor, sometimes I like to move the remote files from Desktop to Laptop to work on them. To make a sort of local cache. This could be individual files or directory trees.

But then I have a mess of duplication. Sometimes I forget to put the files back.

Seems like Laptop could be a lot more clever than I am and help with this. Like could it always fetch a remote file which is being edited and save it locally?

Is there any way to have Laptop fetch files, information about file trees, etc, located on Desktop when needed and smartly put them back after editing?

Or even keep some stuff around. Like lists of files, attributes, thumbnails etc. Even browsing the directory tree on Desktop can be slow sometimes.

I am not sure what this would be called.

Ideas and tools I am already comfortable with:

rsync is the most obvious foundation to work from but I am not sure exactly what would be the best configuration and how to manage it.
luckybackup is my favorite rsync GUI front end; it lets you save profiles, jobs etc which is sweet
freeFileSync is another GUI front end I've used but I am preferring lucky/rsync these days
I don't think git is a viable solution here because there are already git directories included, there are many non-text files, and some of the directory trees are so large that they would cause git to choke looking at all the files.
syncthing might work. I've been having issues with it lately but I may have gotten these ironed out.

Something a little more transparent than the above would be cool but I am not sure if that exists?

Any help appreciated even just idea on what to web search for because I am stumped even on that.

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[–] [email protected] 2 points 5 months ago (1 children)

Hey I’m replying again directly to your post in the hopes that I can push against some of the advice you’re getting. My intent is to do an end run around arguing with the people making these suggestions because they’re very smart and made them for good reasons but their ideas aren’t necessarily good for you and I don’t want you to have to go through a troublesome recovery like I did and many people on the internet have.

Do not under any circumstances set up raid or zpools for your data drives once you get them inside a case and on the pcie bus somehow.

In these configurations accessing a file requires spinning up all the drives in the array or pool. Not only is that putting wear and tear on your drives, it increases the temperature of the case and draws much more power. Those conditions lead to drive failure. When your drive fails and you have a spare to use in its place, resilvering (the process of using extra data called parity to rebuild the contents of the failed drive on the spare one) will put those exact conditions on your remaining drives.

For people like us, who may not have a hot spare, or great cooling, or an offsite backup, an array like that will set us up for failure rather than resilience.

Please consider using mergerfs or something like it and a snapshot parity system like snapraid instead.

There are very good use cases for the raid and zpool systems that have been brought up, but you aren’t there. I got there at moderate expense and moved away from them.

[–] [email protected] 1 points 5 months ago (1 children)

thanks I appreciate it. I've been around the block enough times to expect maximalist advice in places like this. people who are motivated to be hanging around in a forum just waiting for someone to ask a question about hard drives are coming from a certain perspective. Honestly, it's not my perspective. But the information is helpful in totality even though I'm unlikely to end up doing what any one person suggests.

RAID is something I've seen mentioned over and over again. Every year or two I go reading about them more intentionally and never get the impression it's for me. Too elaborate to solve problems I don't have.

[–] [email protected] 2 points 5 months ago (1 children)

good luck. what'd you end up figuring out to access your files quicker?

[–] [email protected] 1 points 5 months ago

TBD

I've been struggling with syncthing for a few weeks... It runs super hot on every device. Need to figure out how to chill it out a bit.

Other than that I'll look at both NFS and WebDAV some more. Then will come back to this page to re read the more intricate suggestions.

[–] [email protected] 2 points 5 months ago

Is the desktop using a wifi card? You could plug it into the router to shorten the journey and halve the number of wireless hops.

[–] [email protected] 9 points 5 months ago

I have a very similar setup to you, and I use SyncThing without issue for the important files (which I keep in my Documents directory to make it easy to remember).

[–] [email protected] 3 points 5 months ago* (last edited 5 months ago) (1 children)

wifi is less responsive than ethernet
You don't even need encryption on local connection(no need for ssh) if it is never global.
if you have that many external HDD, I would rather get a NAS and call it a day, it has everything configured for you as well.
I don't know what big data you access on, get a larger SSD to store whatever you might visit often from your HDDs.

[–] [email protected] 6 points 5 months ago (1 children)

Strong disagreement on №2. That kinda thinking is how you get devices on your home network to join a malicious botnet without your knowledge and more identity theft. ALL network communications should assume that a malicious actor may be present and use encryption-in-transit for anything remotely approaching private, identifiable, or sensitive.

[–] [email protected] 15 points 5 months ago

You can mount remote with rclone and fine tune caching to your liking: https://rclone.org/commands/rclone_mount/#vfs-file-caching

[–] [email protected] 2 points 5 months ago* (last edited 5 months ago) (1 children)

git-annex maybe?

[–] [email protected] 1 points 5 months ago

Or just git depending on the use case.

[–] [email protected] 2 points 5 months ago* (last edited 5 months ago)

i can imagine some kind of LRU cache being reasonably useful for this situation, assuming you have some latency hierarchy. For example if the desktop has an SSD, HDD, and some USB HDDs attached I can imagine you having a smaller cache that keeps more frequently accessed files on the SSD, followed by a bigger one on the internal HDD, and followed again by USB HDDs as the ultimate origin of the data. Or even just have the SSD as cache and everything else is origin. I don't know if there's software that would do this kind of thing already though.

You may want to consider zipping files for transfer though, especially if the transfer protocol is creating new tcp connections for every file.

[–] [email protected] 6 points 5 months ago (1 children)

One of the few times I miss Files-on-demand for Win11. Connect an Office365 library with 500 GB to my laptop with an 128 GB harddrive. Integrates with file explorer, only caches local what you open, after a while you can "free space", meaning deleting local cache version. NextCloud has the same on Win11 because its an OS feature.

[–] [email protected] 2 points 5 months ago (1 children)

sounds sweet! Perfectly what I am looking for.

It's so rare to be jealous of windows users!!

I do find this repo: jstaf/onedriver: A native Linux filesystem for Microsoft OneDrive. So I guess in theory it would be possible in linux? If you could apply it to a different back end..

[–] [email protected] 2 points 5 months ago

It's certainly possible, if not else than with the use of FUSE. But I did not see such a project yet that can do this.

[–] [email protected] 2 points 5 months ago* (last edited 5 months ago) (1 children)

I think others have mentioned TrueNAS as an OS for your Desktop. TrueNAS uses ZFS which is nice cuz it uses RAM to help with speeding up file operations. TrueNAS makes it easy to set up NFS shares if your laptop is running a Unix-like OS, or Samba, for anything else. IDK how much RAM is in your desktop, but if you can get that to 16 or 32 GB, you'd be set on that front.

For dealing with an OS you don't want to change, I'd think about the following first:

What is the speed of your network card in the Desktop? If its 100mbit, you may want to look into upgrading that, if possible to at least a Gigabit card for PCIe. That would speed up anything you do with it.

As for needing local sync for when you're away from your home network, Syncthing could maybe do what you want. TrueNAS can run Syncthing pretty easily as well, but it can be installed on anything, though, idk how this works if you set Syncthing to track a folder thats also one mounted on your local machine via NFS/Samba. Syncthing will just sync the most recent changes to a file to the server, so you can sync when you're on your home network. Assuming that no one will modify the same files on your desktop when you're away.

[–] [email protected] 2 points 5 months ago (1 children)

Thanks! I have gone to look at TrueNAS or FreeNAS a few times over the years. I am dissuaded because hardware-wise they seem expensive. Then on the other hand, they are limited in what they can do.

Comprehension check. Is the below accurate?

TrueNAS is an OS, it would replace Debian.
Main purpose of TrueNAS is to maintain the filesystem
There are some packages available for TrueNAS, like someone mentioned Syncthing supports it
But basically if I run TrueNAS, I will likely need a second computer to run services

Also for comprehension check:

The reason many people are recommending NAS (or WebDAV, NFS, VPN etc) is because with better storage and network infrastructure I would no longer be interested in this caching idea.
Better would be to have solid enough file sharing within the LAN that accessing files located on Desktop from Laptop would work.
The above would be completely plausible

How'm I doing?

[–] [email protected] 2 points 5 months ago* (last edited 5 months ago) (1 children)

There's one thing I forgot to consider in my original reply and I'm sorry for that. With TrueNAS you'd probably have to copy your data off of the existing drives to somewhere else because they will have to be reformatted to create a ZFS pool. I don't know if that is practical for you, so please don't feel like the following is something you must do or anything.

I think you're doing great. Sorry for the late reply. To answer your questions:

TrueNAS Scale is an OS that is built on top of Debian. Using TrueNAS makes set up simpler to set up, but you could implement what you want with a Debian install, but if you were to install TrueNAS, it would replace whatever existing OS you have installd.
Yes, TrueNAS would manage your filesystem. It can manage your hard drives for you. Its UI isn't too hard to understand, and it can be accessed and managed through a web browser on your Laptop.
TrueNAS has some software packages in the form of docker containers, they are managed through the TrueNAS UI. You can browse them though their website here. My advice with these apps would be to set up your NAS with all of the drives in storage pools first before installing these. If theres something you want that isn't supported, TrueNAS can also set up Virtual Machines, and you can use one of those to run those services, provided your CPU supports it and its turned on in the BIOS. If you go need to go down this route, you will have to set up a bridge network in TrueNAS in order to get the VM to communicate with TrueNAS over your network, but that's not particularly hard or anything.
You will need to run TrueNAS on its own computer, yes. What I was suggesting was installing TrueNAS as the OS on your Desktop. Idk if thats practical for you or not, since doing so would need you to wipe everything on the boot drive of your Desktop, so idk if you have a place to copy any important data off of it to.

In terms of comprehension, yeah I think you've got it. I think a NAS system would handle your caching idea for you, if I'm understanding you correctly. Having a good file sharing setup over LAN, whether its using NFS, or Samba would allow you to mount a folder from your Desktop on your Laptop and access them.

For files that you want to have access to when not on your home network, you could set up a folder that Syncthing tracks on your Desktop, sync that with your Laptop, and then have access to them that way.

[–] [email protected] 2 points 5 months ago

thanks for all the details! I've fairly recently done an FS migration that entailed moving all data, reformatting, and moving it all back. Mega pain in the ass. I know more now than I did at the start of that project, so wouldn't be as bad but not getting into something like that lightly.

Though it might be the excuse I need to buy another 12 tb hdd...

[–] [email protected] 12 points 5 months ago (1 children)

This sounds like a setup that is broken in a few ways. First, you need to clean up the desktop. Start by replacing the USB drives. It is a bad idea to use them as they are more likely to fail and have limited speeds. I would get either moderately high RPM hard drives or sata SSDs. Both will be more reliable and have greater speed. Just make sure that they are properly mounted. This is especially important for HDDs as they are very sensitive to vibration and need to be kept still by a proper mount with rubber padding.

For the desktop itself, make sure it is fast enough to provide enough throughput. You should be using a CPU with at least 4 cores and DDR4 memory. The more memory you have the more data can be cached. I would go for 16 or 32gb and if you can go even higher. Also make sure you are using gigabit Ethernet with a gigabit switch.

Now for the software. I would install TrueNAS scale as it uses ZFS which is a create filesystem for data storage. TrueNAS can be a little tricky but it is all controllable though a web interface and if you need help guides can be found online.

For accessing the data, I would use either a SMB or NFS share. Smb tends to be simpler and has better cross platform support. NFS can be faster but it is tricky to configure. Make sure that your laptop has a Ethernet connection as doing things over WiFi is going to be slow. You might be able to get away with it if you have a newer wifi revision with a newer WiFi card.

If you are still looking to solve the original problem, you can use Syncthing. Syncthing has a few click install for TrueNAS and you can find guides on how to configure it in a way that works for you.

[–] [email protected] 2 points 5 months ago (2 children)

Maybe Syncthing is the way forward. I use it for years and am reasonably comfortable with it. When it works, it works. Problems is that when it doesn't work, it's hard to solve or even to know about. For the present use case it would involve making a lot of shares and manually toggling them on and off all the time. And would need to have some kind of error checking system also to avoid deleting unsynced files.

Others have also suggested NFS but I am having a difficult time finding basic info about what it is and what I can expect. How is it different than using SSHFS mounted? Assuming I continue limping along on my existing hardware, do you think it can do any of the local caching type stuff I was hoping for?

Re the hardware, thanks for the feedback! I am only recently learning about this side of computing. Am not a gamer and usually have had laptops, so never got too much into the hardware.

I have actually 2 desktops, both 10+ years old. 1 is a macmini so there is no chance of getting the storage properly installed. I believe the CPU is better and it has more RAM because it was upgraded when it was my main machine. The other is a "small" tower (about 14") picked up cheaply to learn about PCs. Has not been upgraded at all other than SSD for the system drive. Both running debian now.

In another comment I ran iperf3 Laptop (wifi) ---> Desktop (ethernet) which was about 80-90MBits/s. Whereas Desktop ---> OtherDesktop was in the 900-950 MBits/s range. So I think I can say the networking is fine enough when it's all ethernet.

One thing I wasn't expecting from the tower is that it only supports 2x internal HDDs. I was hoping to get all the loose USB devices inside the box, like you suggest. It didn't occur to me that I could only get the system drive + one extra. I don't know if that's common? Or if there is some way to expand the capacity? There isn't too much room inside the box but if there was a way to add trays, most of them could fit inside with a bit of air between them.

This is the kind of pitfall I wanted to learn about when I bought this machine so I guess it's doing its job. :)

Efforts to research what I would like to have instead have led me to be quite overwhelmed. I find a lot of people online who have way more time and resources to devote than I do, who want really high performance. I always just want "good enough". If I followed the advice I found online I would end up with a PC costing more than everything else I own in the world put together.

As far as I can tell, the solution for the miniPC type device is to buy an external drive holder rack. Do you agree? They are sooo expensive though, like $200-300 for basically a box. I don't understand why they cost so much.

[–] [email protected] 2 points 5 months ago (1 children)

2 internal hdds

As I understand the PC case is some sort of small form factor and the motherboard has more SATA ports to plug in disks.

If that's the case then try to find old pc case in the dumpster or from a neighbour. It should have more space for disks.

Some PCs 15 years ago had incompatible layouts so be a little cautious but gratis is a fair price.

[–] [email protected] 1 points 5 months ago (1 children)

Do you mean take the board out of this case and put it in another, bigger one?

I actually do have a larger, older tower that I fished out of the trash. Came with a 56k modem! But I don't know if they would fit together. I also don't notice anywhere particularly suitable to holding a bunch of storage; I guess I would have to buy (or make?) some pieces.

Here is the board configuration for the Small Form Factor:

I did try using #9 and #10 for storage and I seem to recall it kind of worked but didn't totally work but not sure of the details. But hey, at least I can use a CD drive and a floppy drive at the same time!

[–] [email protected] 2 points 5 months ago

As far as I can see you could try to attach 1 ssd to SATA0 (it can dangle in the air) and 2 hard drives to SATA1 and SATA2 (They are capped to 300MB/s and should be attached to the case with screws)

There should be space somewhere to put the drives as I can see in the specification. You will probably need to remove the CD drive.

There is also a question if power supply has enough power sockets to attach to the disks. You could try to find eSATA -> SATA adapter to attach something to the last port.

You probably won't find the bigger case as motherboard isn't standard size.

I would probably try to upgrade to standard motherboard size but I would also calculate the cost of consumed electricity in a year vs cost of more efficient hardware.

[–] [email protected] 3 points 5 months ago* (last edited 5 months ago) (1 children)

Simplify it down if you can. Forget NFS, SSHFS and syncthing as those are to complex and overkill at the moment. SMB is dead simple in a lot of ways and is hard to mess up.

I would start by figuring out how to get more drives in your desktop. SSDs can be put anywhere but HDDs need to be mounted. I would get two big disks and put them in raid 1 and then get a small disk for the boot drive. TrueNAS is still going to be the easiest route and TrueNAS scale is based on Debian under the hood although its designed to not be modified for reliability.

Forget the USB drives. I did that for a while and it is bad in so many ways. It will come back to haunt you even if the work fine for now.

For the desktop you always could upgrade the ram or CPU if that becomes the bottleneck. If the ram is 8gb or less you should upgrade it. Make sure you are getting ram that is fast enough to keep up with the CPU. You can find more information about your CPU and its ram speed online.

For your WiFi, it actually isn't bad. You might be ok using it depending on what you are doing.

For the minipc I wouldn't use it as a NAS. You can but it is probably going to be limiting.

In case your desktop doesn't have enough Sata ports you could get a ePCI sata card. They are pretty cheap ($10) and will potentially work better if your hardware is limited.

[–] [email protected] 0 points 5 months ago* (last edited 5 months ago) (1 children)

Forget NFS, SSHFS and syncthing as those are to complex and overkill at the moment. SMB is dead simple in a lot of ways and is hard to mess up.

OTOH, SSHFS and syncthing are already humming along and I'm framiliar with them. Is SMB so easy or having other benefits that would make it better even though I have to start from scratch? It looks like it (and/or NFS) can be administered from cockpit web interface which is cool.

Now that I look around I think I actually have a bit of RAM I could put in the PC. MacMini's original RAM which is DDR3L; but I read you can put it in a device that wants DDR3. So I will do that next time it's powered off.

Thanks for letting me know I could use an expansion card. I was wondering about that but the service manual didn't mention it at all and I had a hard time finding information online.

Is this the sort of thing I am looking for: SATA Card 4 Port with 4 SATA Cables, 6 Gbps SATA 3.0 Controller PCI Express Expression Card with Low Profile Bracket Support 4 SATA 3.0 Devices ($23 USD) I don't find anything cheaper than that. But there are various higher price points. Assuming none of those would be worthwhile on a crummy old computer like I have. Is there any specific RAID support I should look for?

I have only the most cursory knowledge of RAID but can tell it becomes important at some point.

But am I correct in my understanding that putting storage device in RAID decreases the total capacity? For example if I have 2x6TB in RAID, I have 6 TB of storage right?

Honestly, more than half my data is stuff I don't care too much about keeping. If I lose all the TV shows I don't cry over it. Only some of it is stuff I would care enough to buy extra hardware to back up. Those tend to be the smaller files (like documents) whereas the items taking up a lot of space (media files) are more disposable. For these ones "good enough" is "good enough".

I really appreciate your time already and anything further. But I am still wondering, to what extent is all this helping me solve my original question which is that I want to be able to edit remote files on Desktop as easily as if they were local on Laptop? Assuming i got it all configured correctly, is GIMP going to be just as happy with a giant file lots of layers, undos, etc, on the Desktop as it would be with the same file on Laptop?

[–] [email protected] 1 points 5 months ago* (last edited 5 months ago)

Funny you found that card as I have the same one. I would only spend the extra money if your computer doesn't have enough sata ports.

For raid you do not want hardware raid. It is generally problematic and doesn't have any error correction. Also, if the controller were to die you could be in trouble.

The reason I say TrueNAS is that it makes the setup pretty straight forward. I have never used cockpit for file shares so I do not know if it works well or not. I do no it will require more setup and maintenance. For the software you could setup either a btrfs or ZFS raid 1 config. TrueNAS is ZFS only but it is turned for solid performance in a single job.

The reason I say raid 1 is not because it is a backup. Raid is not a backup and should not be treated as such. What it can offer is reduced downtime. If one drive fails you can simply swap out the drive. If you do not have a redundant copy you either need to recreate the data from a backup or try to do a data recovery operation. I would also recommend that you turn on snapshots as if it really handy to be able to roll back a change quickly. Snapshots are not complete backups but they are a form of version control.

As far as DDR3 goes, it is pretty slow and will not be able to come close to saturating a gigabit connection. Prepare to have slow speeds unfortunately. The good news is that if you get this setup and later decide it is time to upgrade then you can.

[–] [email protected] 4 points 5 months ago (1 children)

What's your network performance look like? 100mbit? Gigabit?
External drives are terribly slow, USB doesn't have great throughout. Also they're unreliable, do you have backups? I'd look into making those drives internal (SATA) which has much better throughput. I use one external drive on USB3 for duplication, and it's noticeably slower on file transfers, like 40%.
For remote access to your files, look into Tailscale. You run it on your laptop and server (or any compatible device in your network), and it provides a virtual mesh network that functions like a LAN between devices.
Syncthing is great, but it just keeps files in, entire folders of them. So if space is tight on the laptop, it won't really help, not easily anyway.
Resilio Sync has Selective Sync, where it can index a folder and store that index on any device participating in that sync job. Then you can select which files to sync at any time.

[–] [email protected] 4 points 5 months ago (1 children)

In another comment I ran iperf3 Laptop (wifi) ---> Desktop (ethernet) which was about 80-90MBits/s. Whereas Desktop ---> OtherDesktop was in the 900-950 MBits/s range. So I think I can say the networking is fine enough when it's all ethernet. Is there some other kind of benchmarking to do?
Just posted a more detailed description of the desktops in this comment (4th paragraph). It's not ideal but for now its what I have. I did actually take the time (gnome-disks benchmarking) to test different cables, ports, etc to find the best possible configuration. While there is an upper limit, if you are forced to use USB, this makes a big difference.
Other people suggested ZeroTier or VPNs generally. I don't really understand the role this component would be playing? I have a LAN and I really only want local access. Why the VPN?
Ya, I have tried using syncthing for this before and it involves deleting stuff all the time then re-syncing it when you need it again. And you need to be careful not to accidentally delete while synced, which could destroy all files.
Resilio I used it a long time ago. Didn't realize it was still around! IIRC it was somewhat based on bittorrent with the idea of peers providing data to one another.

[–] [email protected] 3 points 5 months ago* (last edited 5 months ago)

The VPN is to give you access to your files from anywhere, since you don't have the storage capacity on your laptop for all of them.

If you have an encrypted connection to home, laptop storage isn't a concern.

As a benefit, this also solves the risk of losing files that are only on the laptop, by keeping the at home.

Yea, Syncthing has it's moments (and uses - I keep hundreds of gigs between 5 phones and 5 laptops/desktops in sync with it).

Resilio does use the bittorrent protocol, but uses keys and authorization for shares. Give it a try, it may address your need to access files remotely. I use it to access my media (about 2TB) which clearly can't be sync'd to my laptop (or phone). I can grab any file, at any time.

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