[Galaxy Note 3 Exynos Android Development] iamsuperuser:
I did what you said but still the backup was slow

So I formatted my 64GB sdxc to FAT32

Now the backup time is 4mins 23 secs

Build: samsung/ha3gxx/ha3g:4.4.2/KOT49H/N900XXUDNB2:user/release-keys
Hardware: universal5420
Revision: 11
Bootloader: N900XXUDNB2
Radio: unknown
Kernel: Linux version 3.4.39-halaszk-UNIVERSAL5420-V0.16-IKS-CLUSTER-SM-N900-PWR-CORE (root@halaszk.tk) (gcc version 4.7.4 20130603 (prerelease) (Linaro GCC 4.7-2013.06-1) ) #2 SMP PREEMPT Sun Mar 30 17:35:39 CEST 2014

Starting recovery on (UTC) Tue Apr 1 23:48:36 2014

can't open /dev/tty0: No such file or directory
framebuffer: fd 3 (1080 x 1920)
PhilZ Touch ported by halaszk 6.25.0
Clockworkmod v6.0.4.7
I:Device target: SM-N900
I:Touch GUI revision: 1.16
No /etc/extra.fstab
recovery filesystem table
=========================
0 /boot emmc /dev/block/mmcblk0p9 0
1 /recovery emmc /dev/block/mmcblk0p10 0
2 /system ext4 /dev/block/mmcblk0p20 0
3 /data ext4 /dev/block/mmcblk0p21 0
4 /cache ext4 /dev/block/mmcblk0p19 0
5 /efs ext4 /dev/block/mmcblk0p3 0
6 /modem emmc /dev/block/mmcblk0p13 0
7 /sdcard datamedia /dev/null 0
8 /storage/extSdCard auto /devices/platform/dw_mmc.2/mmc_host/mmc2 0
9 /storage/UsbDriveA auto /devices/platform/exynos-dwc3.0/exynos-xhci.0 0
10 /tmp ramdisk ramdisk 0

W:Unable to get recovery.fstab info for /datadata during fstab generation!
W:Unable to get recovery.fstab info for /emmc during fstab generation!
W:Unable to get recovery.fstab info for /preload during fstab generation!
W:Unable to get recovery.fstab info for /sd-ext during fstab generation!
W:Unable to get recovery.fstab info for /external_sd during fstab generation!
I:Completed outputting fstab.
I:using /data/media/0 for /sdcard
I:Connected to Vold..
I:110 0 extSdCard /storage/extSdCard 1
I:110 0 UsbDriveA /storage/UsbDriveA 0
I:200 0 Volumes listed.
I:Processing arguments.
I:Checking arguments.
I:device_recovery_start()
I:auto_restore_settings set to default (false)
I:check_root_and_recovery set to default (true)
I:compression_value set to default (low)
I:twrp_backup_mode set to default (false)
I:enable_md5sum set to default (1)
I:show_nandroid_size_progress set to default (1)
I:use_nandroid_simple_logging set to default (1)
I:nand_prompt_on_low_space set to default (1)
I:signature_check_enabled set to default (0)
I:install_zip_verify_md5 set to default (0)
I:set_brightness set to default (160)
I:menu_height_increase set to default (40)
I:show_virtual_keys set to default (true)
I:min_log_rows set to default (3)
I:background_image set to default (default)
I:background_image set to default
I:Default stitch background loaded.
I:show_background_icon set to default (false)
I:show_battery set to default (true)
I:show_clock set to default (true)
I:menu_text_color set to default (8)
I:menu_background_color set to default (1)
I:menu_highlight_color set to default (7)
I:normal_text_color set to default (0)
I:menu_separator_color set to default (6)
I:header_text_color set to default (8)
I:batt_clock_color set to default (2)
I:menu_background_transparency set to default (102)
I:menu_highlight_transparency set to default (102)
I:menu_separator_transparency set to default (102)
I:show_menu_separation set to default (true)
I:dim_timeout set to default (60)
I:blank_timeout set to default (180)
I:scroll_sensitivity set to default (80)
I:touch_accuracy set to default (7)
I:touch_to_validate set to default (true)
I:enable_vibrator set to default (true)
I:boardEnableKeyRepeat set to default (true)
I:wait_after_install set to default (true)
I:slide_left_action set to default (5)
I:slide_right_action set to default (3)
I:double_tap_action set to default (2)
I:press_lift_action set to default (4)
I:press_move_action set to default (1)
I:t_zone=5
I:t_zone_offset=30
I:use_dst_time set to default (false)
I:Current time: 2014-04-01 23:48:38 (UTC +5:30)
I:use_qcom_time_daemon set to default (0)
I:use_qcom_time_offset set to default (0)
Command: "/sbin/recovery"

af.resampler.quality=255
ro.sf.lcd_density=480
ro.adb.qemud=1
ro.adb.secure=0
ro.com.google.gmsversion=4.4.2_r1
ro.com.google.clientidbase=android-samsung
ro.com.android.dateformat=MM-dd-yyyy
ro.ril.hsxpa=1
ro.ril.gprsclass=10
ro.sec.fle.encryption=true
ro.boot.sec_atd.tty=/dev/ttySAC2
ro.boot.selinux=enforcing
ro.boot.serialno=4d00a4f9b87690a9
ro.boot.bootloader=N900XXUDNB2
ro.boot.debug_level=0x4f4c
ro.boot.warranty_bit=1
ro.boot.emmc_checksum=3
ro.boot.odin_download=1
ro.hwui.path_cache_size=8
ro.hwui.layer_cache_size=32
ro.hwui.shape_cache_size=2
ro.hwui.texture_cache_size=48
ro.hwui.gradient_cache_size=1
ro.hwui.drop_shadow_cache_size=4
ro.hwui.text_large_cache_width=4096
ro.hwui.text_small_cache_width=2048
ro.hwui.text_large_cache_height=2048
ro.hwui.text_small_cache_height=1024
ro.hwui.texture_cache_flushrate=0.5
ro.semc.xloud.supported=true
ro.somc.sforce.supported=true
ro.somc.clearphase.supported=true
ro.wifi.channels=
ro.allow.mock.location=0
ro.board.platform=exynos5
ro.build.id=KOT49H
ro.build.PDA=N900XXUDNA6
ro.build.date=Tue Jan 14 13:57:57 KST 2014
ro.build.date.utc=1389675477
ro.build.host=SWDC3402
ro.build.tags=release-keys
ro.build.type=user
ro.build.user=dpi
ro.build.scafe=americano
ro.build.scafe.shot=double
ro.build.scafe.size=short
ro.build.display.id=KOT49H.N900XXUDNA6
ro.build.product=ha3g
ro.build.selinux=1
ro.build.selinux.enforce=1
ro.build.version.sdk=19
ro.build.version.release=4.4.2
ro.build.version.codename=REL
ro.build.version.incremental=N900XXUDNA6
ro.build.changelist=376474
ro.build.hidden_ver=N900XXUDNA6
ro.build.description=ha3gxx-user 4.4.2 KOT49H N900XXUDNA6 release-keys
ro.build.fingerprint=samsung/ha3gxx/ha3g:4.4.2/KOT49H/N900XXUDNA6:user/release-keys
ro.build.characteristics=phone
ro.error.receiver.default=com.samsung.receiver.error
ro.hdcp2.rx=tz
ro.slook.ver=1
ro.config.knox=1
ro.config.tima=1
ro.config.ringtone=Over_the_horizon.ogg
ro.config.alarm_alert=Alarm_Morning_flower.ogg
ro.config.media_sound=Media_preview_Touch_the_light.ogg
ro.config.notification_sound=S_Whistle.ogg
ro.crypto.state=unencrypted
ro.kernel.qemu=0
ro.secure=0
ro.secwvk=220
ro.carrier=unknown
ro.product.cpu.abi=armeabi-v7a
ro.product.cpu.abi2=armeabi
ro.product.name=ha3gxx
ro.product.board=universal5420
ro.product.brand=samsung
ro.product.model=SM-N900
ro.product.device=ha3g
ro.product.locale.region=GB
ro.product.locale.language=en
ro.product.manufacturer=samsung
ro.service.swiqi3.supported=true
ro.baseband=unknown
ro.bootmode=unknown
ro.chipname=exynos5420
ro.hardware=universal5420
ro.opengles.version=196608
ro.revision=11
ro.serialno=4d00a4f9b87690a9
ro.bootloader=N900XXUDNB2
ro.bootloader.mode=download
ro.debuggable=1
ro.debug_level=0x4f4c
ro.factorytest=0
ro.setupwizard.mode=DISABLED
ro.product_ship=true
ro.warranty_bit=1
ro.emmc_checksum=3
ro.securestorage.support=true
dev.pm.dyn_samplingrate=1
net.bt.name=Android
net.change=net.bt.name
init.svc.adbd=running
init.svc.vold=running
init.svc.healthd=running
init.svc.ueventd=running
init.svc.postinit=running
init.svc.recovery=running
init.svc.setup_adbd=stopped
rild.libargs=-d /dev/ttyS0
rild.libpath=/system/lib/libsec-ril.so
media.enable-commonsource=true
media.aac_51_output_enabled=true
dalvik.vm.heapsize=512m
dalvik.vm.heapmaxfree=8m
dalvik.vm.heapminfree=2m
dalvik.vm.dexopt-flags=m=y
dalvik.vm.heapstartsize=8m
dalvik.vm.heapgrowthlimit=128m
dalvik.vm.stack-trace-file=/data/anr/traces.txt
dalvik.vm.heaptargetutilization=0.75
tunnel.decode=true
tunnel.audiovideo.decode=true
persist.adb.notify=0
persist.sys.ui.hw=true
persist.sys.usb.config=mtp,adb
persist.sys.dalvik.vm.lib=libdvm.so
persist.sys.country=GB
persist.sys.language=en
persist.sys.timezone=Asia/Kolkata
persist.sys.clssprld1=706
persist.sys.clssprld2=724
persist.sys.localevar=
persist.sys.profiler_ms=0
persist.sys.setupwizard=FINISH
persist.sys.flipfontpath=/data/data/com.android.settings/app_fonts/Samsungsans#Samsung Sans
persist.sys.use_dithering=1
persist.sys.storage_preload=2
persist.audio.sysvolume=9
persist.audio.ringermode=2
persist.audio.allsoundmute=0
persist.audio.hphonesysvolume=9
persist.audio.headsetsysvolume=9
persist.radio.icc.cb.list=
persist.radio.icc.cb.count=0
persist.radio.initphone-type=1
persist.service.cdrom.enable=0
persist.service.xloud.enable=1
persist.service.swiqi3.enable=1
persist.speaker.prot.enable=false
persist.security.ams.enforcing=1
selinux.reload_policy=0
service.adb.root=1
keyguard.no_require_sim=true

I:Checking for extendedcommand & OpenRecoveryScript...
I:Skipping execution of extendedcommand, file not found...
I:Skipping execution of OpenRecoveryScript, file not found...
I:605 Volume extSdCard /storage/extSdCard state changed from 1 (Idle-Unmounted) to 3 (Checking)
/storage/extSdCard: Checking
I:613 extSdCard /storage/extSdCard "0485-D940"
I:614 extSdCard /storage/extSdCard
I:605 Volume extSdCard /storage/extSdCard state changed from 3 (Checking) to 4 (Mounted)
/storage/extSdCard: Mounted
I:200 0 volume operation succeeded
Couldn't open directory /storage/extSdCard/clockworkmod/backup/
No files found.
I:ro.modversion set to default (noname)
I:ro.romversion set to default (noname)
I:ro.build.display.id=KOT49H.N900XXUDNB2
I:setting up /data/media(/0) for /sdcard/clockworkmod/.default_backup_format.
I:using /data/media/0 for /sdcard
I:Checking needed space for backup '/storage/extSdCard/clockworkmod/backup/2014-04-01.23.49.21_KOT49H.N900XXUDNB2'
I:failed to get device mmcblk link '/dev/block/mmcblk0p10'
I:/recovery backup size (/proc)=8Mb
I:failed to get device mmcblk link '/dev/block/mmcblk0p9'
I:/boot backup size (/proc)=8Mb
I:/system backup size (stat)=1235Mb
I:/cache backup size (stat)=5Mb
I:/data: tot size=26619Mb, free=25895Mb, backup size=585Mb, used=590Mb, media=5Mb
I:/storage/extSdCard/.android_secure backup size=0Mb

>> Free space: 57383Mb (94%)
>> Needed space: 1841Mb

>> Backing up /boot...
Backing up boot image...
Backup of boot image completed.

>> Backing up /recovery...
Backing up recovery image...
Backup of recovery image completed.
I:setting up /data/media(/0) for /sdcard/clockworkmod/.hidenandroidprogress.
I:using /data/media/0 for /sdcard

>> Backing up /system...

Press Back to cancel.
I:setting up /data/media(/0) for /sdcard/clockworkmod/.ignore_nandroid_secontext.
I:using /data/media/0 for /sdcard
I:setting up /data/media(/0) for /sdcard/clockworkmod/.ignore_nandroid_secontext.
I:using /data/media/0 for /sdcard
backing up selinux context...
backup selinux context completed.
Backup of system completed.
I:setting up /data/media(/0) for /sdcard/clockworkmod/.hidenandroidprogress.
I:using /data/media/0 for /sdcard

>> Backing up /data...

Press Back to cancel.
I:setting up /data/media(/0) for /sdcard/clockworkmod/.ignore_nandroid_secontext.
I:using /data/media/0 for /sdcard
I:setting up /data/media(/0) for /sdcard/clockworkmod/.ignore_nandroid_secontext.
I:using /data/media/0 for /sdcard
backing up selinux context...
backup selinux context completed.
Backup of data completed.
I:setting up /data/media(/0) for /sdcard/clockworkmod/.hidenandroidprogress.
I:using /data/media/0 for /sdcard

>> Backing up /storage/extSdCard/.android_secure...

Press Back to cancel.
I:setting up /data/media(/0) for /sdcard/clockworkmod/.ignore_nandroid_secontext.
I:using /data/media/0 for /sdcard
I:setting up /data/media(/0) for /sdcard/clockworkmod/.ignore_nandroid_secontext.
I:using /data/media/0 for /sdcard
Backup of .android_secure completed.
I:setting up /data/media(/0) for /sdcard/clockworkmod/.hidenandroidprogress.
I:using /data/media/0 for /sdcard

>> Backing up /cache...

Press Back to cancel.
I:setting up /data/media(/0) for /sdcard/clockworkmod/.ignore_nandroid_secontext.
I:using /data/media/0 for /sdcard
I:setting up /data/media(/0) for /sdcard/clockworkmod/.ignore_nandroid_secontext.
I:using /data/media/0 for /sdcard
backing up selinux context...
backup selinux context completed.
Backup of cache completed.
I:No sd-ext found. Skipping backup of sd-ext.

>> Generating md5 sum...
> boot.img
> cache.context
> cache.ext4.tar
> cache.ext4.tar.a
> data.context
> data.ext4.tar
> data.ext4.tar.a
> recovery.img
> system.context
> system.ext4.tar
> system.ext4.tar.a
> system.ext4.tar.b
chmod: /storage/extSdCard/clockworkmod/blobs: No such file or directory
Finalizing, please wait...
I:setting up /data/media(/0) for /sdcard/clockworkmod/.default_backup_format.
I:using /data/media/0 for /sdcard

Backup complete!
Backup time: 04:23 mn
Backup size: 1797.79Mb
Compression: 0.00%
press any key to continue.
Rebooting...
I:setting up /data/media(/0) for /sdcard/clockworkmod/.recovery_version.
I:using /data/media/0 for /sdcard
I:ro.build.version.sdk=19
I:setting up /data/media(/0) for /sdcard/clockworkmod/.no_confirm.
I:using /data/media/0 for /sdcard

But in FAT32 file system file transfer speeds from PC to Sd card are low compared to exFAT

So I would request you to add support for exFAT in recovery.

Thanks in advance.