Suffering is not a part of the creation of the almighty Lord Sri Krishna.
The Lord not only created a beautiful world full of joys, but also gave an instructions manual "The Bhagavad Gita", which elaborately explains how every living being can live peacefully and happily.
The Bhagavad Gita is littered with pure knowledge.
As man ignores the teachings of The Bhagavad Gita, he embraces sufferings.
The Lord demonstrates this by dividing the time in this material world into four Yugas
Satya Yuga, when the majority of the population accepts The Bhagavad Gita, there is hardly any kind of sufferings.
Treta Yuga, when some percentage of the population rejects The Bhagavad Gita, sufferings appear.
Dwapara Yuga, when more people reject The Bhagavad Gita, more sufferings.
Kali Yuga, when a large majority of the poulation rejects The Bhagavad Gita, sufferings, sufferings and more sufferings. That is what we are witnessing now.