System installation: Attempt to install Ubuntu together with Windows (dual boot) on my Dell XPS 13 9370

I am aware of a series of related questions and solutions, but I am about to try them all without success.

Recently, I updated SSD on my Dell XPS 13 and expected to go to dual boot configuration. I started with the installation of Windows 10; There were some problems, I was not detecting the new SSD. I have read somewhere that I should change the SATA operation in BIOS from RAID ON to AHCI. I did it and installed Windows without any other problems. I reduced the Windows partition and left 50 GB of unallocated space. Then I downloaded Ubuntu, made a bootable USB with Rufus and tried to install it.

Here is my problem in a nutshell. I can't install Ubuntu from USB: Ubuntu starts the USB, but when I try to install it, it doesn't detect my SSD. The solution to this that seems to work for other people is to change from RAID ON to AHCI, but I have already done so. I also checked the Windows Device Manager storage drivers and in fact it is what it is supposed to be (according to this:
I also did all kinds of related things in the BIOS: enable usb boot, disable safe boot, change Fastboot to Thorough, etc. I have also disabled Fastboot in Windows Power Options and made sure it is not hibernating, that seems to block the drive in some way.
I also tried using different ports for my USB adapter (all are USB-C but 2 of them are also Thunderbolt3).

If anyone has an idea of ​​how I can fix it, I would be very grateful.

data – How do I save a trie in memory in a Spring Boot application?

I have a spring boot application, which simply does it, takes a character set and lists the possible English words.
Now, as everyone knows, it is quite easy to build a data structure to load a dictionary.

Now, the problem is, say 170,000 words in the English dictionary, it needs to be in memory, how can I achieve it?

Most of the time I have used databases in memory like H2 with spring boot, but I'm not sure how I would store a file in the database.

Other caches (such as redis) store the key-value data structure, since trie is not a key-value pair, I am not sure how to store it.

Any suggestions would be welcome.

boot – Installing Ubuntu with rEFInd instead of Grub2

Preface: I have found quite a few posts here and there that address fragments of my particular problem, but I have not found a complete enough answer that can calm my worries.

My intention is to install Ubuntu cleanly on a new GPT disk, using rEFInd to start Ubuntu and any other operating system that I can install later (for example, Arch, Gentoo, Windows and whatever you may need). I can partition the disk in advance using another system, configuring the ESP, the root and perhaps a swap partition for Ubuntu. If possible, I can also install rEFInd on the ESP at this point.

I know that Ubuntu can be installed without Grub (using ubiquity --no-bootloader, if still valid), but I'm not sure what to do after this point. rEFInd is supposedly easy to configure, but I'm not sure how to configure things like boot and kernel parameters, or any configuration junk that usually enters Grub.

What I am looking for is a list of things that I would need to consider and configure in this particular configuration, while reducing the headache later (for example, updating the kernel).

Additional question: What happens if the installation mode is to copy a preconfigured disk image (specific to this computer), which already has a Grub configuration? How should I get rid of it and replace it with rEFInd, while maintaining any important boot / kernel configuration that Grub has to remove?

dual boot – Install along with win7 what partitions do I need to configure?

I have an unallocated partition of 40 GB in my c: drive. It may be a bit much but it's fine.
I am looking to install Ubuntu 19. I have seen some guides that I need to define exchange and root things. I'm a Linux baby, so I really don't know what it really takes.
Final answer?
16 GB of RAM, don't worry about hibernating if that matters.

Re-configuring the PC to boot from the hard drive

In Windows 10, I configured my PC to boot from a DVD containing the Ubuntu operating system.
Now I need to reconfigure, in the BIOS, the PC to boot from the hard drive again.
How can I do that? Using Windows 10. Thank you very much for your help!

Boot – Unpacking initramfs failed: write error

I am trying to put Ubuntu on an old HP Pavilion zt1130, which has a Celeron i686 processor. I used an Ubuntu MATE 16.04 disk that was out there. However, I received the error:

initramfs unpacking failed: write error

I've seen this before, so I got a blank DVD and recorded a new copy of vanilla Ubuntu 16.04. I booted on the CD and got the same error! I have also tried using the forcepae boot parameter that often works miracles on old machines, but has the same error. I am not an expert, so I cannot say what is happening here. I would really appreciate the help.

bootcamp – Choosing Windows in the boot manager freezes the computer

Trying to install Windows 8.1 on a Mac Pro 10.11.6 in early 2009 (Mac Pro4.1 model identifier) ​​with a DVD because the USB shows only EFI boot, and that requires me to flash my Mac to 5.1. (Also read that USB does not work with a Mac Pro in early 2009)

When I start my computer the message "There is no boot device: insert the boot disk and press any key" and I have not been able to see my DVD, if I enter the Startup Manager (pressing the / alt option while booting) I have Windows and Efi boot to choose from, if I press windows my computer freezes and nothing happens and efi boot shows me loading files 2 times and then a black screen.

I checked the DVD with cmp /Users/Win8.1.iso /dev/disk4 and he got cmp: EOF on /Users/Win8.1.iso which is probably only filled with zeros, which happens when the image is smaller than the size of the DVD. I also checked md5 From the DVD and the iso file and I got different results, after thinking that the DVD was damaged, I recorded another DVD with a different recorder and had the same md5 checksum as the previous DVD.

So my question is this: did I burn the DVD badly or is there another problem? Is there any other way to install Windows other than DVD, or a simple way to install with EFI boot?

junit: in Spring Boot Test, how do I assign a temporary folder to a configuration property?

I want to do a self-cleaning test

In my situation, I have one of the components that depends on a directory

public class FileRepositoryManagerImpl implements ....

    private File basePath;


The value is defined in the application.yml file, and in DEV points to a directory under build.

This is not the worst idea, because gradle clean it will eventually clean up the mess created by the evidence.

But, really, what I would like to achieve here, is to make sure that each test is run in an isolated temporary directory that is cleaned after execution.

I know that JUnit has a tool for temporary directories. But once I have defined that directory in the scope of JUnit 4, how do I tell Spring to use that temporary directory?

I tried the inner class without success:

@SpringBootTest(classes = { SecurityBeanOverrideConfiguration.class, App.class })
public abstract class AbstractFileRepositoryManagerIntTests {

    private final static TemporaryFolder temporaryFolder = new TemporaryFolder();

    public static TemporaryFolder getTemporaryFolder()
        return temporaryFolder;

    @ConfigurationProperties(prefix = "acme")
    static class Configuration

        public FileRepository getFileRepository()
            return new FileRepository();

        static class FileRepository

            public File basePath() throws Exception
                return temporaryFolder.newFolder("fileRepositoryBaseDir");

I was thinking about retouching with the Environment, but what should be the correct way to inject properties programmatically in a Spring Boot test?

Macos: How much space do I need to make a Catalina boot volume on my Mac Mojave?

I am thinking of installing Catalina in a Volume to test and I wondered how much space this new operating system will occupy on my Mac.

I am planning to use APFS Volume so that both my main Macintosh HD and user data remain intact and only install Catalina to search now, so suppose I don't need to worry about two copies of my user data or applications, just the bare OS for install and try to boot to look around without running the migration wizard.

What space should I consider to install a clean installation of MacOS Catalina without user data or applications?

bootcamp – The Boot Camp wizard "needs more disk space" although I have enough

Trying to get a dual boot for my mac and I encountered this problem.

Not enough storage

And when I look at the state of my unit, this is what I see.

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So maybe I'm doing something wrong, but it doesn't seem right that I need "at least 39 GB" when I have 46 GB available

Anyway, I plan to update this Mac's storage soon anyway if I can't solve this