USB detected slowly and does not auto mount in Ubuntu 18.04

I have recently installed Xubuntu 18.04 on my Dell Studio 1558 laptop, and I find that by USB is now taking a long time to be detected and does not get auto mounted by the file manager. It used to work fine with the 17.XX version of Xubuntu.

I find that right after plugging in the USB, dmesg shows that it has detected the USB, but the entry in /dev is created only after some time. Even after the entry gets created (/dev/sdb), it is not auto mounted. I can manually mount the USB and it is accessible after that.

I have checked dconf editor for auto mount options and they look fine. The drive does not show up in Disks utility either.

Following are my observations:

dmesg and other command output (right after plugging in the USB)

 privat@privat-Studio-1558:~$   lsblk NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT sda      8:0    0 298.1G  0 disk ├─sda1   8:1    0  39.2M  0 part ├─sda2   8:2    0  14.7G  0 part ├─sda3   8:3    0 104.8G  0 part ├─sda4   8:4    0     1K  0 part ├─sda5   8:5    0   7.9G  0 part └─sda6   8:6    0 170.7G  0 part / sr0     11:0    1  1024M  0 rom  privat@privat-Studio-1558:~$   sudo fdisk -l [sudo] password for privat: Disk /dev/sda: 298.1 GiB, 320072933376 bytes, 625142448 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x06d985af  Device     Boot     Start       End   Sectors   Size Id Type /dev/sda1  *           63     80324     80262  39.2M de Dell Utility /dev/sda2           80325  30800324  30720000  14.7G 83 Linux /dev/sda3        30800325 250624148 219823824 104.8G 83 Linux /dev/sda4       250626046 625141759 374515714 178.6G  5 Extended /dev/sda5       608653312 625141759  16488448   7.9G 82 Linux swap / Solaris /dev/sda6       250626048 608653311 358027264 170.7G 83 Linux  Partition table entries are not in disk order.  privat@privat-Studio-1558:~$   df -h Filesystem      Size  Used Avail Use% Mounted on udev            3.9G     0  3.9G   0% /dev tmpfs           784M  1.4M  783M   1% /run /dev/sda6       168G   15G  145G  10% / tmpfs           3.9G   23M  3.9G   1% /dev/shm tmpfs           5.0M  4.0K  5.0M   1% /run/lock tmpfs           3.9G     0  3.9G   0% /sys/fs/cgroup tmpfs           784M   16K  784M   1% /run/user/1000  dmesg snippet:  [  445.202900] usb 2-1.3: new high-speed USB device number 3 using ehci-pci [  445.323808] usb 2-1.3: New USB device found, idVendor=0781, idProduct=5567, bcdDevice= 1.00 [  445.323811] usb 2-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [  445.323812] usb 2-1.3: Product: Cruzer Blade [  445.323813] usb 2-1.3: Manufacturer: SanDisk [  445.323815] usb 2-1.3: SerialNumber: 4C530000210213115415  privat@privat-Studio-1558:~$   lsusb Bus 002 Device 003: ID 0781:5567 SanDisk Corp. Cruzer Blade Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 004: ID 0c45:6416 Microdia Bus 001 Device 006: ID 413c:8162 Dell Computer Corp. Integrated Touchpad [Synaptics] Bus 001 Device 005: ID 413c:8161 Dell Computer Corp. Integrated Keyboard Bus 001 Device 003: ID 0a5c:4500 Broadcom Corp. BCM2046B1 USB 2.0 Hub (part of BCM2046 Bluetooth) Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub  lshw          *-usb:0              description: USB controller              product: 5 Series/3400 Series Chipset USB2 Enhanced Host Controller              vendor: Intel Corporation              physical id: 1a              bus info: pci@0000:00:1a.0              version: 06              width: 32 bits              clock: 33MHz              capabilities: pm debug ehci bus_master cap_list              configuration: driver=ehci-pci latency=0              resources: irq:16 memory:f0b06000-f0b063ff            *-usbhost                 product: EHCI Host Controller                 vendor: Linux 5.0.0-31-generic ehci_hcd                 physical id: 1                 bus info: usb@1                 logical name: usb1                 version: 5.00                 capabilities: usb-2.00                 configuration: driver=hub slots=3 speed=480Mbit/s               *-usb                    description: USB hub                    product: Integrated Rate Matching Hub                    vendor: Intel Corp.                    physical id: 1                    bus info: usb@1:1                    version: 0.00                    capabilities: usb-2.00                    configuration: driver=hub slots=6 speed=480Mbit/s                  *-usb:0                       description: USB hub                       product: BCM2046B1                       vendor: Broadcom                       physical id: 1                       bus info: usb@1:1.1                       version: 1.00                       capabilities: usb-2.00                       configuration: driver=hub maxpower=94mA slots=3 speed=12Mbit/s                     *-usb:0                          description: Keyboard                          product: Integrated Keyboard                          vendor: Dell Computer Corp.                          physical id: 1                          bus info: usb@1:1.1.1                          version: 1.00                          capabilities: usb-2.00                          configuration: driver=usbhid maxpower=2mA speed=12Mbit/s                     *-usb:1 UNCLAIMED                          description: Mouse                          product: Integrated Touchpad [Synaptics]                          vendor: Dell Computer Corp.                          physical id: 2                          bus info: usb@1:1.1.2                          version: 1.00                          capabilities: usb-2.00                          configuration: maxpower=2mA speed=12Mbit/s                  *-usb:1                       description: Video                       product: Laptop_Integrated_Webcam_2M                       vendor: M092S-H02-0525-SC48Q                       physical id: 4                       bus info: usb@1:1.4                       version: a1.15                       capabilities: usb-2.00                       configuration: driver=uvcvideo maxpower=168mA speed=480Mbit/s  

After some time, I see the /dev/sdb entry. Output of commands after this:

 dmesg snippet:  [  445.202900] usb 2-1.3: new high-speed USB device number 3 using ehci-pci [  445.323808] usb 2-1.3: New USB device found, idVendor=0781, idProduct=5567, bcdDevice= 1.00 [  445.323811] usb 2-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [  445.323812] usb 2-1.3: Product: Cruzer Blade [  445.323813] usb 2-1.3: Manufacturer: SanDisk [  445.323815] usb 2-1.3: SerialNumber: 4C530000210213115415 [  815.370890] usb-storage 2-1.3:1.0: USB Mass Storage device detected [  815.371165] scsi host5: usb-storage 2-1.3:1.0 [  815.371305] usbcore: registered new interface driver usb-storage [  815.412954] usbcore: registered new interface driver uas [  816.382630] scsi 5:0:0:0: Direct-Access     SanDisk  Cruzer Blade     1.00 PQ: 0 ANSI: 6 [  816.383044] sd 5:0:0:0: Attached scsi generic sg2 type 0 [  816.384110] sd 5:0:0:0: [sdb] 122585088 512-byte logical blocks: (62.8 GB/58.5 GiB) [  816.385620] sd 5:0:0:0: [sdb] Write Protect is off [  816.385623] sd 5:0:0:0: [sdb] Mode Sense: 43 00 00 00 [  816.386606] sd 5:0:0:0: [sdb] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA [  816.401129]  sdb: sdb1 [  816.404620] sd 5:0:0:0: [sdb] Attached SCSI removable disk  privat@privat-Studio-1558:~$   lsblk NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT sda      8:0    0 298.1G  0 disk ├─sda1   8:1    0  39.2M  0 part ├─sda2   8:2    0  14.7G  0 part ├─sda3   8:3    0 104.8G  0 part ├─sda4   8:4    0     1K  0 part ├─sda5   8:5    0   7.9G  0 part └─sda6   8:6    0 170.7G  0 part / sdb      8:16   1  58.5G  0 disk └─sdb1   8:17   1  58.5G  0 part sr0     11:0    1  1024M  0 rom  privat@privat-Studio-1558:~$   sudo fdisk -l Disk /dev/sda: 298.1 GiB, 320072933376 bytes, 625142448 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x06d985af  Device     Boot     Start       End   Sectors   Size Id Type /dev/sda1  *           63     80324     80262  39.2M de Dell Utility /dev/sda2           80325  30800324  30720000  14.7G 83 Linux /dev/sda3        30800325 250624148 219823824 104.8G 83 Linux /dev/sda4       250626046 625141759 374515714 178.6G  5 Extended /dev/sda5       608653312 625141759  16488448   7.9G 82 Linux swap / Solaris /dev/sda6       250626048 608653311 358027264 170.7G 83 Linux  Partition table entries are not in disk order.     Disk /dev/sdb: 58.5 GiB, 62763565056 bytes, 122585088 sectors Units: sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disklabel type: dos Disk identifier: 0x00000000  Device     Boot Start       End   Sectors  Size Id Type /dev/sdb1          32 122585087 122585056 58.5G  c W95 FAT32 (LBA)  privat@privat-Studio-1558:~$   lsusb Bus 002 Device 003: ID 0781:5567 SanDisk Corp. Cruzer Blade Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 001 Device 004: ID 0c45:6416 Microdia Bus 001 Device 006: ID 413c:8162 Dell Computer Corp. Integrated Touchpad [Synaptics] Bus 001 Device 005: ID 413c:8161 Dell Computer Corp. Integrated Keyboard Bus 001 Device 003: ID 0a5c:4500 Broadcom Corp. BCM2046B1 USB 2.0 Hub (part of BCM2046 Bluetooth) Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub 

The drive is not auto mounted even after this. Manual mount works fine:

 privat@privat-Studio-1558:~$   sudo mount /dev/sdb1 /media/usb 

I am wondering why the /dev entry might be getting installed slowly, and auto mount does not seem to work.

Thanks in advance for any insights.

How to auto scale plot

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25448251500000 - 535526010000 x + 5077310000 x^2 - 36775800 x^3 +    250890 x^4 - (6199 x^5)/5 + (17 x^6)/5 - x^7/250 + 920347020000 y -    16448410100 x y + 122367000 x^2 y - 607718 x^3 y + (15694 x^4 y)/   5 - (7099 x^5 y)/500 + (9 x^6 y)/250 - (x^7 y)/25000 +    15128205050 y^2 - 220083300 x y^2 + 1275939 x^2 y^2 - (   19598 x^3 y^2)/5 + (8699 x^4 y^2)/1000 - (11 x^5 y^2)/500 + (   x^6 y^2)/50000 + 152047500 y^3 - 1691358 x y^3 + 7640 x^2 y^3 - (   96 x^3 y^3)/5 + (13 x^4 y^3)/500 - (x^5 y^3)/25000 + 1032409 y^4 - (   40191 x y^4)/5 + (119 x^2 y^4)/5 - (11 x^3 y^4)/250 + (x^4 y^4)/   50000 + (24094 y^5)/5 - (12299 x y^5)/500 + (9 x^2 y^5)/250 - (   x^3 y^5)/25000 + (14699 y^6)/1000 - (23 x y^6)/500 + (x^2 y^6)/   50000 + (13 y^7)/500 - (x y^7)/25000 + y^8/50000 +    5089650300000 Sin[x] - 107105202000 x Sin[x] +    1015462000 x^2 Sin[x] - 7355160 x^3 Sin[x] + 50178 x^4 Sin[x] -    6199/25 x^5 Sin[x] + 17/25 x^6 Sin[x] - (x^7 Sin[x])/1250 +    133172901000 y Sin[x] - 2218630000 x y Sin[x] +    14318780 x^2 y Sin[x] - 47992 x^3 y Sin[x] + 6299/50 x^4 y Sin[x] -    9/25 x^5 y Sin[x] + (x^6 y Sin[x])/2500 + 1693912000 y^2 Sin[x] -    21830360 x y^2 Sin[x] + 112000 x^2 y^2 Sin[x] -    304 x^3 y^2 Sin[x] + 12/25 x^4 y^2 Sin[x] - (x^5 y^2 Sin[x])/1250 +    13470380 y^3 Sin[x] - 119968 x y^3 Sin[x] + 408 x^2 y^3 Sin[x] -    4/5 x^3 y^3 Sin[x] + (x^4 y^3 Sin[x])/2500 + 71778 y^4 Sin[x] -    10199/25 x y^4 Sin[x] + 17/25 x^2 y^4 Sin[x] - (x^3 y^4 Sin[x])/   1250 + 12299/50 y^5 Sin[x] - 21/25 x y^5 Sin[x] + (x^2 y^5 Sin[x])/   2500 + 12/25 y^6 Sin[x] - (x y^6 Sin[x])/1250 + (y^7 Sin[x])/2500 ==   0