update README for isa-l and libdeflate

Author: Shifu Chen

README.md

@@ -19,8 +19,8 @@ Citation: Shifu Chen. 2023. Ultrafast one-pass FASTQ data preprocessing, quality
   - [install with Bioconda](#install-with-bioconda)
   - [or download the latest prebuilt binary for Linux users](#or-download-the-latest-prebuilt-binary-for-linux-users)
   - [or compile from source](#or-compile-from-source)
-    - [Step 1: download and build libisal](#step-1-download-and-build-libisal)
-    - [step 2: download and build libdeflate](#step-2-download-and-build-libdeflate)
+    - [Step 1: install isa-l](#step-1-install-isa-l)
+    - [step 2: install libdeflate](#step-2-install-libdeflate)
     - [Step 3: download and build fastp](#step-3-download-and-build-fastp)
 - [input and output](#input-and-output)
   - [output to STDOUT](#output-to-stdout)
@@ -114,20 +114,20 @@ chmod a+x ./fastp
 ## or compile from source
 `fastp` depends on `libdeflate` and `libisal`, while `libisal` is not compatible with gcc 4.8. If you use gcc 4.8, your fastp will fail to run. Please upgrade your gcc before you build the libraries and fastp.
 
-### Step 1: download and build libisal
-See https://github.com/intel/isa-l
-`autoconf`, `automake`, `libtools`, `nasm (>=v2.11.01)` and `yasm (>=1.2.0)` are required to build this isal
+### Step 1: install isa-l
+It's recommended that to install it using your package manager, for example `apt install isa-l` on ubuntu, or `brew install isa-l` on Mac. Otherwise you can compile isa-l from source. Please be noted that `isa-l` is not compatible with gcc 4.8 or older versions. See https://github.com/intel/isa-l
+`autoconf`, `automake`, `libtools`, `nasm (>=v2.11.01)` and `yasm (>=1.2.0)` are required to build this isa-l
 ```shell
 git clone https://github.com/intel/isa-l.git
 cd isa-l
 ./autogen.sh
 ./configure --prefix=/usr --libdir=/usr/lib64
-make
+make -j
 sudo make install
 ```
 
-### step 2: download and build libdeflate
-See https://github.com/ebiggers/libdeflate
+### step 2: install libdeflate
+It's recommended that to install it using your package manager, for example `apt install libdeflate` on ubuntu, or `brew install libdeflate` on Mac. Otherwise you can compile isa-l from source. See https://github.com/ebiggers/libdeflate
 ```shell
 git clone https://github.com/ebiggers/libdeflate.git
 cd libdeflate
@@ -143,7 +143,7 @@ git clone https://github.com/OpenGene/fastp.git
 
 # build
 cd fastp
-make
+make -j
 
 # Install
 sudo make install